Lepidoptera-Skippers and Moths

The question is frequently asked what is the difference between a butterfly, moth and skipper?  Butterflies are typically day fliers, brightly colored and typically possess a knob on the tip of their antennae. On the other hand moths are typically nocturnal (active at night,) mostly dull colored and lack the knob at the tip of the antennae.  As with butterflies skippers are day fliers, frequently brightly colored but differ from the true butterflies in that they possess proportionately larger bodies, smaller wings, and hooked antennae. The difference in coloration of butterflies and moths is functionally associated with their mating behaviors.  Day fliers utilize coloration in distinguishing and attract the opposite sex of in a given species.  Color is not readily distinguishable at night.  Consequently moths utilize chemicals (sex pheromones to attract the opposite sex.

Lepidoptera contains more than 180,000 species in 128 families. The name is derived from Ancient Greek λεπίδος (scale) and πτερόν (wing). Estimates of species suggest that the order may have more species and is among the four largest, successful orders, along with the Hymenoptera, Diptera, and the Coleoptera.

Species of the order Lepidoptera are commonly characterized as being covered in scales, having two large compound eyes, and an elongated mouthpart called a proboscis. The larvae are called caterpillars and are characterized by a cylindrical body with a well developed head, mandible mouthparts, and from 0–11 (usually 8) legs.

                                                                             Family-Hesperidae. Skippers 

There are over 3500 species in this family occurring worldwide. These "ancient" butterflies are frequently confused with moths. Their clubbed antennae are frequently hooked and their wings are usually folded back along the body. These small butterflies have large eyes and fly rapidly.                                                                            

Fiery Lawn Skipper-Hylephila phyleus. The most common species in California is the fiery lawn skipper.  Skippers are also characterized (as their name suggests) by their rapid, darting flight. It is distinguishable by its very short antennae and wingspan (1 1/8 - 1 1/4 inches). Males are a fiery yellowish-orange with black, toothed margins while the females exhibit a darker brown base coloration. A wide black stigma (a gland that releases pheromones to attract females) is visible on the upper forewing. Females are yellowish-brown with small, dusky, dark spots. They are common on golf courses and are abundant around residential lawns. They range throughout California, south through Baja California and northern Mexico, and east toward the Atlantic states.

Life Cycle. Eggs are laid singly, and larvae feed on lawn grasses, especially preferring Bermuda grass. The caterpillars are densely covered with short hairs and are distinguishable by their relatively large, dark heads, which look to be segmented from their bodies. They are hard to spot, however, as they roll and tie leaves of grass around them to create shelters in the underlayer of the grass. Adults like to sun themselves with their wings partially spread and their fore and hindwings separated.

                                                                                                                                              

                                                                                                              Figure .  Male fiery lawn skipper adults.  Image courtesy Wikipedia.

Control.  Reducing thatch and overseeding with varieties of non-preferred grass species will both minimize larval feeding and buildup. A drench test (see UC IPM online) can be used to determine damaging populations. If more than 15 larvae are found per square yard treatment may be needed.

                                                                                   Tortricidae. Tortricid Moths.

This is the fourth largest family of Lepidoptera. Many of the adults are described as bell shaped, taking on the shape of the liberty bell (Figure   ).  A large percentage of the species are leaf rollers or leaf folders, living inside leaves.  As their names imply they roll or fold the leaves of their host plant in which they subsequently live for protection from potential enemies. Other larvae feed inside stems and fruit.  The family contains many pest species, including the codling moth and the oriental fruit moth.

                                                                                         

                                                                    A typical bell shaped Tortricid moth.  Image courtesy Entomart2, Wikipedia.

Codling Moth-Cydia pomonella.  It is native to Europe and was introduced to North America, where it has become one of the regular pests of apple orchards. It is found almost worldwide. It also attacks pears, walnuts, and other tree fruits.

The adult is grayish with light grey and copper stripes on its wings, and has an average wingspan of ¼ inch in length. The females lay eggs on fruit or leaves and the black-headed yellow larvae attack the fruit immediately upon hatching. Each larva burrows into the fruit, eats for around three weeks, then exits the fruit to overwinter and pupate elsewhere. Most nourishment is obtained by feeding on the seeds. The Codling Moth typically exhibits 2 generations per year in most regions of the USA - in the Pacific Northwest there is a partial third.

 A synthetic version of its sex pheromone (codlemone) is now commercially available.  Pheromone traps are used to monitor field populations of this pest. This in combination with day degree models peak or beginning adult emergence of the adults in the field can be precisely predicted thus allowing timely use of control measures, including the use of pesticides.

One technique that has been used to control this pest is referred to as mating disruption.  Sex pheromones are used by the female to attract the male for mating.  This is the only way mating can occur sin the male does not visually recognize the female. The control technique consists of saturating entire apple orchard with the smell of artificially produced sex pheromone over the entire growing season. The purpose of this procedure is to prevent the male moths from finding females and consequently preventing mating and reproduction. If this can be accomplished, the moths will not reach sufficient numbers to become pests. Two theories as to why this technique works have been called the male confusion technique and the male inhibition technique. The male confusion theory is based on the premise that is if the air of a field is saturated with artificially produced sex pheromone, when female releases her pheromone in that field, there will be no discernible odor plume for him to follow and find her. The male inhibition theory is based on a biological phenomenon that is common to many animals including humans and moths. For example, when someone is continuously exposed to a strong odor (e.g. perfume or cologne), after a short period of time, one can no longer smell it. This is because the olfactory sense cells in the nose adapt to the presence of this odor. The same phenomenon would occur in a male moth sitting in a field saturated with the smell of artificial pheromone. If a female moth released her pheromone in that field, a male would not be able to detect it and therefore could not find her to mate.

Since codling moth larvae feed deep in the apple they are not readily available to the various predators and parasites of biological control. However,  Trichogramma wasps. The wasps deposit their eggs into codling moth eggs, and the developing wasp larvae consume the moth embryo inside.

Another method for control and sampling, 'trunk banding', consists of wrapping a corrugated cardboard strip around the tree trunk. Larvae making their way back to the tree to pupate after the infested fruits are aborted will use bands as pupation sites. Bands may then be removed and burned.

Recent trials of non-toxic kaolin clay-based sprays indicate that an effective alternative means of codling moth suppression may be on the horizon. Codling moth and other pests find leaves and fruit covered in kaolin clay unfit for laying eggs. Tiny particles of the clay tend to attach to their bodies, disturbing and repelling them. In addition, trees covered in kaolin clay can make them less recognizable as habitat to codling moths. Full coverage of trees is necessary in order to achieve effective suppression. If used only at the beginning of the fruit growing season, kaolin clay often comes off by itself due to wind and rain attrition, leaving fruit clean at harvest time.

                                                                                  
                                                                   Codling Moth Adult. Images left to right  courtesy of Olaf Leillinger and USDA

Oriental Fruit Moth-Cydia molesta. The oriental fruit moth originated in China. It was introduced in the United States from Japan on flowering cherry about 1913 and is now found in all fruit growing regions of the United States, southern Canada and northern Mexico. It is also common throughout Europe, Asia, Australia and South America. The larvae bore in shoots or feed in fruit.

 

                                                                                                                                                                 

                                                              Oriental Fruit Moth Larva and Stem Damage.  Clemson University - USDA Cooperative Extension Slide Series, Bugwood.org

 

Although the primary hosts of the oriental fruit moth are peach and nectarine, it will also attack quince, apricot, apple, plum, cherry, pear, rose and flowering cherry. While common in some eastern apple-growing districts, infestations of apple are rare in the Northwest. The egg is a small, flat, oval disc, which is white at first but changes to amber. The larva has 4 or 5 instars. The newly hatched larva is white or cream with a black head. When full grown, it measures 3/8 to 1/2 inch (8 to 13 mm). It has a brown head capsule and thoracic shield and a pinkish or creamy white body. It can be distinguished from a codling moth larva by the presence of an anal comb (comb-like structure on the underside of the last abdominal segment.), which is lacking in the codling moth larva. The adult oriental fruit moth is gray and measures about 1/4 inch (5 mm). The wings have indistinct light and dark bands, giving the moth a salt-and-pepper appearance. The oriental fruit moth overwinters as a fully grown larva in silk webbing, either in tree crevices or in the ground cover. It pupates in the spring. Moths of the overwintering generation first appear when peach is in bloom. Eggs are laid on the foliage, usually on the upper sides of leaves of terminal growth. A female can produce up to 200 eggs. Incubation can take anywhere from 5 to 21 days depending on the temperature. 

First generation larvae feed by boring into the growing shoots. They reach maturity by mid- to late May. First generation moth flight is from early June through mid-July. There are 3 to 4 flights per year in Washington. Some second and most third and fourth generation larvae attack fruit before seeking overwintering sites where they spin cocoons.

First and second generation larvae tend to damage mainly shoots, while most of the injured fruit is due to third and fourth generation larvae. The oriental fruit moth attacks succulent terminals of rapidly growing twigs during spring and early summer.  A newly hatched larva enters the tender, growing shoot at its tip, near the base of a young leaf. An immature larva that has abandoned an old, injured twig enters a new one at the axel of a fully developed leaf. The larva bores inside the twig, working its way down the shoot for 2 to 6 inches (5 to 15 cm). When the larva matures or no longer finds the twig desirable, it makes an exit hole and leaves. If it needs more food to develop fully, it may enter another twig or a fruit.

 Infested twigs usually have wilted leaves. If an upright twig has one small, wilted leaf, it means the larva has entered within the last day or two. As the larva moves down into the twig, more leaves wilt. The number depends how far the larva penetrates. If a twig is dark colored or has dry leaves and gummy ooze, the larva has left. When twigs of young trees are attacked, lateral shoots form below the damage. Young trees under severe and continued attack become bushy. In nurseries, shoots of recently budded peach are sometimes attacked, resulting in crooked stems. 

Fruit of peach and nectarine can be damaged early in the season by partly grown larvae after they leave shoots. They usually feed on the side of the fruit, causing gumming with brown sawdust-like frass. As fruit grow, they become deformed, and the more severely damaged fruit may drop. Fruit are more often attacked when nearing maturity. Newly hatched larvae usually, though not always, enter through the stem end. They bore through the flesh to the pit of peaches and nectarines, where most of the feeding is done. When mature, larvae move to the fruit surface, making a round exit hole. Larvae feed only on one fruit and do not move from fruit to twigs. 

Apples infested with oriental fruit moth larvae look similar to those infested by codling moth. However, the codling moth larva tunnels directly to the core and feeds on the seeds, whereas the burrows of oriental fruit moth are smaller and follow a more meandering course, not necessarily to the core. Oriental fruit moth larvae do not push frass to the surface of infested fruits as do codling moth larvae.

Monitoring. Damage to shoot tips looks like that caused by the peach twig borer. Examine growing shoot tips while the first generation larvae are active. Infested shoots will be wilted. Pheromone traps can be used to monitor adult moths. Traps should be placed in the orchard prior to peach bloom and monitored daily until the first moth is observed. Good trap maintenance and care are important for good information.

 
Control. The braconid wasp Macrocentrus ancylivorus, which is native to North America, is a leaf-roller parasite that has adapted to the oriental fruit moth. Females lay eggs in young oriental fruit moth larvae. The larva of the parasitoid larva develops and matures when the host cocoons.

 
Chemical control of the oriental fruit moth can be improved by using a degree-day model to establish optimum timing, as with codling moth. The target of control sprays is the young larvae before they have bored into shoots or fruit.

 

Moth capture in a pheromone trap is used to establish Biofix, the start of degree-day accumulation. When the first moth is captured, the degree-day total is set at zero. According to research in California, the best time to apply control sprays is between 500 and 600 degree-days after biofix. Good control of the first generation larvae in late April or early May may mean no further controls are necessary for the rest of the year. The generation of oriental fruit moth lasts about 1000 degree-days. Thus, if sprays are required for the second generation they should be applied at 1500 to 1600 degree-days after biofix. These degree-day timings have not been thoroughly tested in Washington but have worked very well in California. 

Mating Disruption.  Mating disruption has proven to be a successful control for oriental fruit moth. Dispensers should be placed in the orchard before the April moth flight. In warm years, or in orchards with high moth populations or outside pressure, a second application of dispensers may be needed. Dispenser types that last only 2 months may also require multiple applications.

 

Mexican Jumping Bean Moth- Cydia deshaisiana. This is a moth from Mexico that is most widely known as its larva, where it inhabits the carpels of seeds from several species of the shrub genus Sebastiania (S. pavoniana or S. palmeri). These seeds are commonly known as Mexican jumping beans. The moth lays the egg on the young pod. The hatched larva gnaws into the seed, which closes the minute hole during its growth. The larva attaches itself to the bean with many silken threads by hooks on its anal and four hind abdominal prolegs. When the bean is abruptly warmed, for instance by being held in the palm of the hand, the larva twitches and spasms, pulling on the threads and causing the characteristic hop. "Jump" is often an exaggeration, but the beans nonetheless do move around quite a bit. The larva may live for months inside the bean with varying periods of dormancy. It eats away the inside of the bean, making a hollow for itself. If the seed is cut, the larva will repair the hole with silk.  If the larva has adequate conditions such as moisture, it will live long enough to go into a pupal stage. In preparation to this, it eats a circular hole through the shell in February and closes it again with a silken plug. This is to enable the jawless adult moth to escape from the seed. After completion of the exit hole it spins a cocoon within the seed, with a passage way leading to the door. During the following pupal stage the larva will not move any more. Normally in the spring, the moth will force its way out of the bean through a round "trap door", leaving behind the pupal casing. The small, jawless silver and gray-colored moth will live for only a few days.

 

                                                                                                                      

                                                                                 Mexican Jumping Bean Moth and Its Bean. Image en Wikipedia.

Western Spruce Budworm is the most destructive defoliator of coniferous forests in Western North America. It is now widely distributed throughout the Rocky and Coast Mountains. The first recorded outbreak was in 1909 on the southeastern part of Vancouver Island in British Columbia, Canada. Since that year, infestations have frequently been reported in western Canada

This budworm was first recorded in 1914 in the United States, in Oregon. However, it was not initially recognized as a serious threat to coniferous forests in the western U.S. Aerial spraying apparently terminated some smaller epidemics in the southern and central Rockies; others subsided naturally. The insect then appeared to be dormant in US forests until 1922, when two outbreaks were reported near Priest Lake in northern Idaho. Since then, significant outbreaks in the Rockies and in the Pacific Northwest have caused top-killing and serious economic losses in tree growth. Tree mortality from budworm can occur in regeneration, sapling, and pole-sized trees. Trees in mature stands severely defoliated by the western spruce budworm may become susceptible to bark beetles, which kill mature trees.

Considered the most destructive defoliator in British Columbia, sustained outbreaks of the Western Spruce Budworm resulted in defoliation of over 247,105 acres in the Fraser Canyon - Lillooet - Pemberton area from 1949-58. From 1970 -2001 further outbreaks occurred over a much larger area including the area of the previous outbreaks, as well as the Thompson and South Okanagan areas in 1970-2001.

There is no typical pattern for Western Spruce Budworm epidemics. Most of the early epidemics subsided naturally after a few years. Others persisted longer, but without spreading over large areas. An epidemic which began in 1949 in the northern Rocky Mountains has persisted for over 30 years despite insecticidal treatment of more than 6,000,000 acres between 1952 and 1966.

Adult moths are about ¹/₂ inch long and have a wing-spread of ⁷/₈ to 1¹/₈ inches. Moths of both sexes are similar in appearance, although the females are a bit more robust than males. The gray- or orange-brown forewings are banded or streaked, and each usually has a conspicuous white dot on the wing margin.

Larvae develop through 6 instars. Newly hatched larvae are yellow-green with brown heads. In the next three stages, larvae have black heads and collars and orange- or cinnamon-brown bodies. In the fifth stage, larvae have reddish-brown heads marked with black triangles, black collars, and pale olive-brown bodies marked with small whitish spots. Mature larvae are 1 to 1¹/₄ inches long, with tan or light chestnut-brown heads and collars and olive- or reddish-brown bodies with large ivory-colored areas.

                                                                                                                                       

                                                                                                                                     Adult of Western spruce budworm.  Image courtesy of PD-USGOV-USDA-FS 

Throughout most of its range, the Western Spruce Budworm completes one generation a year. Moths emerge from pupil cases usually in late July or early August; in the southern Rockies, adults often begin emerging in early July. The adults mate, and within 7 to 10 days, the female deposits her eggs and then dies. Each female deposit approximately 150 eggs, usually on the underside of conifer needles. Eggs are laid in one to three-row masses containing a few to 130 eggs, with an average of 25 to 40 eggs per mass.

Larvae hatch from eggs in about 10 days. They do not feed, but seek sheltered places under bark scales or in and among lichens on the tree bole or limbs. Here, they spin silken tents in which they remain inactive through the winter. In early May to late June, larvae leave their silken tent to search for food. They first mine or tunnel into year-old needles, closed buds, or newly developing vegetative or reproductive buds.

New foliage, which is normally the preferred food, is usually entirely consumed or destroyed before larvae will feed on older needles. Larvae become full grown usually in early July about 30 to 40 days after leaving their overwintering sites. Larvae pupate in webs of silk they have spun either at the last feeding site or elsewhere on the tree. The pupal stage usually lasts about 10 days. The eastern version of the Spruce Budworm is Choristoneura fumiferana, which is one of the most destructive native insects in the northern spruce and fir forests of the Eastern United States and Canada.

Control.  Budworm populations are usually regulated naturally by combinations of several natural factors such as insect parasites, vertebrate and invertebrate predators, and adverse weather conditions. During prolonged outbreaks when stands become heavily defoliated, starvation can be an important mortality factor in regulating populations.

This species is a favored food of the Cape May Warbler, which is therefore closely associated with its host plant, Balsam Fir. This bird, and the Tennessee and Bay-breasted Warblers, which also have a preference for budworm, lay more eggs and are more numerous in years of budworm abundance.

Natural enemies are probably responsible for considerable mortality when budworm populations are low, but seldom have a regulating influence when populations are in epidemic proportions.

Chemical insecticides such as malathion, carbaryl, and acephate can substantially reduce budworm. Microbial insecticides such as the bacterium Bacillus thuringiensis, a naturally occurring, host-specific pathogen that affects only the larvae of lepidopterous insects is environmentally safe to use in sensitive areas such as campgrounds or along rivers or streams where it may not be desirable to use chemical insecticides.

                                                                                   Lymantriidae-Tussock Moths

The Tussock Moth caterpillars are voracious eaters capable of defoliating entire forests. The most famous family member must be the Gypsy Moth, an introduced species to North America. This critter alone costs millions of dollars to control each year in the United States.  Tussock moth caterpillars are known for their striking tufts of hair, or tussocks. Many species exhibit four characteristic clumps of bristles on their backs, giving them the appearance of a toothbrush. Some have longer pairs of tufts near the head and rear. Judged by looks alone, these fuzzy caterpillars seem harmless, but touch them with a bare finger and you'll feel you've been pricked by fiberglass. A few species, like the Brown-tail, will leave you with a persistent and painful rash. Tussock Moth adults are often dull brown or white. Females are usually flightless, and neither males nor females feed as adults. They focus on mating and laying eggs, dying within days.

                                                                                                

                                                                                                    Figure.  A tussoclk moth caterpillars.  Image Wikipedia.

Douglas-fir Tussock Moth, Orgyia pseudotsugata.  This is one of several important species of tussock moths in the western US.  Most exhibit similar damage and biologies. The larvae chew the needles of spruces, Douglas fir and true firs. During outbreaks they may cause extensive defoliation, with injury typically first concentrated at the top of the tree. Older caterpillars may rapidly defoliate a tree and tops may be killed, sometimes after only a single season of severe injury. Following repeated attacks over several seasons whole trees may die or be weakened to the point of inviting fatal attacks by bark beetles. In the western US this insect is most important as a forest pest in the Northwest. Douglas-fir tussock moth caterpillars also can cause problems because the larval hairs can be irritating and are capable of producing a painful rash. Individual reactions to the hairs are highly variable with some people reacting strongly following exposure while others have little reaction.

A mature larva is 1.2-1.4 inches long, with a gray to brown body and shiny black head. Two long tufts of black hairs project forward from the head, and a similar tuft projects backward from the rear of the body. Dense, light brown patches of hairs and red spots occur on the first four and the last abdominal segment and there is an orange stripe on each side. The cocoon surrounding the pupal stage is brownish gray and covered with hairs from the body of the larva. Cocoons usually are attached to foliage but may be found on tree trunks, rock, or other objects in the vicinity of a previously infested tree. The adult males are moths with rusty-colored forewings and gray-brown hind wings, with a wing-span of about one inch. Females are thick-bodied and wingless, found in close association with the spot where they earlier pupated.

 

                                                                                                 

 

                                                                                                  Douglas Fir Tussock Moth Larvae. Image courtesy of melchoir.

The egg mass, laid on the pupal cocoon of the female, contains about 300 white spherical eggs laid in several layers. The entire mass is covered with a frothy substance that is intermixed with body hairs of the mother. Movement of Douglas-fir tussock moth into new locations around the state sometimes result from humans incidentally moving construction materials or other items that have attached egg masses.

Douglas-fir tussock moth spends the winter as an egg within the egg mass with hatching occurring in the spring, often in late May, typically following bud break. The small, hairy caterpillars migrate, moving to the new growth but also often dispersing upwards in the trees. This latter habit results in some of the caterpillars to be disperse by winds, which will carry the small, hairy caterpillars. Since the adult female moths do not fly, wind-blown movement of young larvae is an important means of initiating new infestations.

The caterpillars first feed solely on the newer foliage, and partially eaten needles may wilt and turn brown. Later, the older caterpillars will move to older needles as the more tender needles are consumed. During feeding, particularly when disturbed, larvae may drop from branch to branch on long silken strands. By mid-July or August, the larvae are full grown and many may migrate from the infested tree. They pupate in brownish spindle-shaped cocoons in the vicinity of the infested trees.

In forests another defoliating insect, the western spruce budworm, favors the same hosts as Douglas-fir tussock moth and often occurs coincidently with it. As these two develop on slightly different schedules - tussock moth egg hatch usually lags behind the initiation of budworm larval feeding in the spring by as much as 3 weeks - care should be taken to properly identify the two and determine which is the more damaging. This becomes particularly important if controlling actions are needed. Applying insecticides for one species at the ideal timing of the other may result in effective treatments for both.

The adults emerge from late July through mid-August. The males are winged and are strong fliers, but the females have only minute, non-functional wings. Mating occurs in the immediate vicinity of the female pupal case. There is one generation produced per year.

Management in Landscape Plantings. Outbreaks of Douglas-fir tussock moth are cyclical due to effects of several natural controls. At least seven species of parasitic wasps and a tachinid fly have been identified as parasites that are locally present. Caterpillars may be killed by general predators, notably spiders. A nuclear polyhedrosis virus disease, known as the “wilt disease”, also can be an important mortality agent during outbreaks. Bird predation on tussock moth caterpillars is considerable during the early larval stages but the longer, dense hairs on larger caterpillars makes predation by most bird species difficult. In addition, severe weather, particularly following egg hatch, can be important in limiting Douglas-fir tussock moth populations. The cumulative effects of these natural controls rarely allow Douglas fir outbreaks to persist more than a couple of years before reverting to a normal non-damaging population level.

Surveying the site for the presence of egg masses in winter and early spring provides an outbreak potential estimate. When egg masses are easily found in the vicinity of known host trees, a higher risk exists for subsequent injury. However, trees should be monitored shortly after bud break to confirm the presence of a potentially damaging population. Chemical controls can be effective but need to be applied thoroughly to the top of the tree. In addition, younger larvae are much more effectively controlled than older larvae, so treatment timing is best shortly after eggs have hatched. In landscape plantings, pyrethroids such as permethrin (Astro), cyfluthrin (Tempo), bifenthrin (Talstar, Onyx) and lambda-cyhalothrin (Scimitar) are effective against Douglas-fir tussock moth caterpillars. Carbaryl (Sevin, Sevimol), teburenozide (Confirm, Mimic) and spinosad (Conserve) are alternative treatments that can provide good control.

Gypsy Moth-Lymantria dispar. Gypsy moth was introduced from Europe into Medford, Massachusetts in 1869 by Leopold Trouvelot, who was attempting to breed the insect for silk production. Unfortunately, some of the caterpillars escaped from his backyard rearing facility, and by the early 1900's they began defoliating large areas of New England.

Damage. This insect is responsible for millions of acres of defoliation annually. Although white, chestnut, black and red oak are preferred, gypsy moth caterpillars also eat hundreds of other tree and shrub species including oak, apple, alder, aspen, basswood, birch, poplar, willow, hawthorn, hemlock, tamarack (larch), pine, spruce, and witch hazel. Gypsy moth usually avoids ash, butternut, black walnut, locust, sycamore, and yellow poplar (tulip tree). Although it usually takes more than one year of defoliation before trees die, conifers that are defoliated may be killed after a single season.

Gypsy moth has one generation per year. Female moths lay egg masses on tree boles, branches, vehicles, houses, and other structures, and this aids their spread to new areas. Egg masses are buff-colored after they are initially deposited in late summer, but they become lighter in color as they bleach in the sun. Egg mass size may indicate population trends. When populations are declining, most egg masses are around ½ inch long and contain about 100 eggs, while building populations have 1 ½ inch long egg masses containing up to a thousand eggs. Gypsy moths survive the winter in the egg stage and hatch in the spring.

Caterpillars have five pairs of blue spots, followed by six pairs of brick red spots on their dorsal surface. They also have a thin yellow median stripe along the length of their back. Tiny, young caterpillars are windblown to their food plants, where they will feed day and night. Older stages of the caterpillars feed only at night to avoid drying out or being eaten by predators. During the day, they rest under leaf litter and bark crevices near the bottom of the tree. Older caterpillars are able to eat conifers, while younger stages are usually found on deciduous hosts.

Mature caterpillars pupate in the summer. Mice, shrews, and ground beetles eat the pupae, and are an important regulator of gypsy moth in this stage. Adult gypsy moths emerge about two weeks after pupating. Adults only live about a week, and do not feed. Female gypsy moths use chemicals to attract a mate soon after they emerge. They lay eggs about a day after mating. Adult gypsy moth males have feathery antennae and brown wings and are able to fly, while cream-colored females of European gypsy moths cannot fly and have threadlike antennae. There is also an Asian variety of gypsy moth with flying females that have luckily been eradicated in Western North America on several occasions following accidental introductions.

Various natural environmental factors help control gypsy moth in North America. A disease-causing fungus known as Entomophaga maimaiga was first introduced in 1910-1911 to control gypsy moth. This fungus only affects select families of moth caterpillars that encounter infected soil and plants or through contact with other infected caterpillars. The spores of the fungus germinate in the spring and work best if rain is abundant. E. maimaiga was responsible for widespread gypsy moth mortality in 1989 and 1990, when wetter than normal conditions were reported in May. Since this time, E. maimaiga has become a significant regulator of gypsy moth populations at both low and high densities. Researchers are unsure whether the increased prevalence of the fungus is due to its initial introduction or if it is the result of a more recent reintroduction into the US. Older gypsy moth caterpillars that die as a result of the fungus die in a vertical position with their legs sticking outward.

A nucleopolyhedrosis virus (LdMNPV) kills enough gypsy moth caterpillars when populations are high to eventually end an outbreak. Caterpillars must eat the viral particles in order to become infected. Caterpillars infected with LdMNPV die in an inverted V position, which explains why the common name for LdMNPV is "the wilt". The activity of LdMNPV is specific in that it only kills gypsy moth caterpillars.

A large metallic green ground beetle known as Calosoma sycophanta was introduced into New England from Europe for gypsy moth control in 1906.  C. sycophanta larvae and adults eat older gypsy moth caterpillars that rest in the leaf litter during the daytime.

                                                                                                  

                                                 Adult male Gypsy moth.  Images courtesy Entomart2 (left) and USDA Photo Library (right).

In an attempt to keep this pest out of California and other western states the USDA has set strict quarantines. These quarantines require that all outdoor household articles be inspected for gypsy moth life stages prior to transportation from an infested area into the state of California.  Failure to inspect household articles is a violation of USDA quarantine regulations and may result in significant civil penalties.  The main stage they are looking for is the egg masses which are frequently deposited on cars, trailer and other outdoor articles

                                                                                 Browntail Moth-Euproctis chrysorrhoea

History. The browntail moth was accidently introduced into Somerville, Massachusetts from Europe in 1897. By 1913, the insect had spread to all of the New England states and New Brunswick and Nova Scotia. Since that time, populations of this pest slowly decreased due to natural controls until the 1960's, when browntail moth was limited to Cape Cod and a few islands off the Maine coast in Casco Bay.

Damage. The larval stage (caterpillar) of this insect feeds on the foliage of hardwood trees and shrubs including: oak, shadbush, apple, cherry, beach plum, and rugosa rose. Larval feeding causes reduction of growth and occasional mortality of valued trees and shrubs. While feeding damage may cause some concern, the primary human impact from the browntail moth is the result of contact with poisonous hairs found on the caterpillars. These tiny (0.15mm) poisonous hairs capable of causing dermatitis similar to poison ivy on sensitive individuals. People may develop the dermatitis or skin rash directly from contact with the larvae or indirectly from contact with airborne hairs. The hairs become airborne either from being dislodged from living or dead larvae or may be associated with the cast skins which result from larval molting. Most people affected by the hairs develop a localized rash which will last for a few hours up to a few days, but on some sensitive individuals the rash can be severe and persist for weeks. The rash results from both a chemical reaction to a toxin in the setae and a physical irritation as the barbed setae become embedded in the skin. Respiratory distress from inhaling the hairs has been reported (11% of the population in one health survey) and can be very serious.

Life History. The browntail moth produces one generation a year. It has four life stages; egg, larval, pupal, and adult. The larval or caterpillar stage lasts for 9 months of the year from August through June. In the fall, colonies of larvae build nests in trees constructed from a single leaf wrapped tightly with large amounts of white silk. A colony consists of 25 to 400 or more larvae. The larvae overwinter within the web nests which are two to four inches long and are situated on branch tips. Eastern tent caterpillar tents which are often confused with these winter nests are found in crotches and forks of apple and cherry tree branches during the spring.

In the spring, as soon as the earliest leaf buds open, the larvae become active and crawl out of their nests to feed on the tender foliage. They may devour the foliage as fast as it develops. For a time the larvae crawl back into the web at night, but as they become larger they remain on the leaves. By late June, larvae are full grown. Large larvae, about 1 1/2 inches long, are dark brown and have a broken white stripe on each side of the body and conspicuous, unpaired, reddish spots on the posterior end of the back. These should not be confused with larvae of the eastern tent caterpillar which has a single, solid, white stripe down its back or the gypsy moth which has paired blue and red spots on its back.

In late June, the larvae spin rough cocoons in which to pupate. The pupae develop into moths which emerge from the cocoons in July. The moths have a wingspread of about 1 1/2 inches. Wings and midsection are pure white. The abdomen (rear part of the body) is brown with a conspicuous tuft of brown hairs at the tip.

After emerging, the females lay eggs in masses on the underside of leaves and cover the eggs with brown hairs from their bodies. Each female lays 200 to 400 eggs. The eggs hatch during August or early in September and the young larvae feed for a short time on the leaves before building their winter webs. This fall feeding does little damage to the trees.

Control. Control of browntail moth populations in isolated instances may be obtained by clipping the overwintering webs and destroying these webs by either soaking in water and detergent or burning them. This control should be undertaken in the fall and winter, from September to late March. Should populations increase to such proportions as to make hand clipping impractical, pesticide application may be necessary. The pesticides should be applied as directed, when caterpillars are present and feeding, from early May through the end of June. Products containing carbaryl, methoxychlor, acephate or other insecticide registered to control pests on shade trees, shrubs, and ornamentals around the home should provide acceptable control results. Only registered fruit tree formulations should be used on apple and other fruit trees. Any pesticide used should be applied according to directions on the label and all precautions should be followed.

                                                                                            

                                                                                           Adult brown tail moth.  Images courtesy Cyware.

Lasiocampidae- Lappet Moths.  The Lasiocampidae family of moths are also known as eggars, snout moths or lappet moths. There are over 2000 species worldwide, and probably not all have been named or studied. Their common name 'snout moths' comes from their unique protruding mouth parts of some species that resemble a large nose. They are called 'lappet moths' due to the decorative skin flaps found on the caterpillar's prolegs. The name 'eggars' comes from the neat egg-shaped cocoons of some species. Caterpillars of this family are large in size and are most often hairy, especially on their sides. Most have skin flaps on their prolegs and a pair of dorsal glands on their abdomen. They feed on leaves of many different trees and shrubs and often use these same plants to camouflage their cocoons. Some species are called Tent caterpillars due to their habit of living together in nests spun of silk. As adults, the moths in this family are large bodied with broad wings and may still have the characteristic elongated mouth parts, or have reduced mouthparts and not feed as adults. They are either diurnal or nocturnal.

                                                                     

                                                               

  Western Tent Caterpillar Larvae and Adult.  Rignt an Left Image courtesy of Jerry Payne USDA/ARs and Whitney Crabshaws, Colorado, State Univ.,  Bugwood, respectively.

Western Tent  Caterpilla- Malacosmoma californicum. Tent caterpillars attack several kinds of broadleaf trees and shrubs and produce unsightly webs, or tents, which detract from the home landscape. Trees with substantial defoliation will have reduced growth and vigor. Caterpillars also can be very common and thus a nuisance as they move around the exterior of a home. The key to eliminating tent caterpillar problems is early detection and use of appropriate cultural or chemical control measures. Although there are many species the eastern tent caterpillar, Malacosoma americanum, and the western tent caterpillar, M. californicum, build large tents and are the most common and damaging in the US..  These species are closely related and have very similar life histories.

Tent caterpillar larvae are attractively colored and more than 1 1/2 inches long. They have a few long hairs on their bodies, mostly along the sides. The species can be easily identified by larval coloration and markings. The eastern tent caterpillar has a solid white line down the center of its back while the western tent caterpillar exhibits a variety of markings and colors, but always has a series of white dashes down the middle of its back.     Adult tent caterpillars are brown and yellowish moths with two diagonal markings on the front wings (Figure 5). Their wingspread is about 1 inch. They are attracted to lights and can occasionally be very abundant. The moths live for only a few days, during which they mate and lay eggs. Adults do not feed.

Tent caterpillars attack a variety of plants, both ornamental and fruit. The eastern tent caterpillar prefers cherry, plum, peach, apple, Hawthorne and related plants. It occasionally attacks other trees, such as oaks, if food is scarce. The western tent caterpillar is found on a variety of trees and shrubs, including oaks and wild plums.

In late spring or early summer, female moths deposit an egg mass encircling small twigs or on tree trunks (Figure 1). Egg masses are present on trees during most of the summer, fall and winter. The adult moth uses a sticky, frothy substance called spumaline as an adhesive to attach eggs to bark or twigs. This substance quickly hardens and possibly protects the egg from desiccation and attack from parasites and predators.   Caterpillars, or larvae, hatch in early spring about the time host plants begin to produce leaves. The eastern tent caterpillar and western tent caterpillar feed on new leaves, forming small webs within a few days after hatching and enlarging the webs as they grow. The web or tent is most often in a crotch of small limbs, and serves as a refuge for the larvae during the night and during rainy spells. Larvae can move considerable distances from the tents to feed As a result damage can occur some distance from the web.  Tent caterpillars feed in groups, thus concentrating their defoliation.
Late in the spring the last instar larvae wander considerable distances and feed on a variety of tree, shrubs and even herbs before finding a site for pupation. Cocoons are formed in the web, under bark, in dead plant material on the ground, or inside a rolled leaf. Forest tent caterpillars often draw leaves together to form a cocoon site. Cocoons are loosely constructed of silk and have a white or yellowish crystalline substance scattered throughout the mass. Cocoons should not be handled since the crystalline substance may cause skin irritation, especially to people with allergies. There is only one generation of tent caterpillars per year.

Control. Control programs should be based on the need to eliminate unsightly webs defoliation and/or nuisance from caterpillars. A combination of cultural and chemical techniques may be necessary. Trees should be inspected for tent caterpillar egg masses during winter pruning. Egg masses appear as swellings on small, bare twigs. Normal pruning often can remove tent caterpillar eggs before they hatch. 

Webs may be pruned out when first noticed in the spring. If they are located in areas where pruning is not desirable or possible, the tent may be destroyed by hand. Use a long pole with nails extending from it to destroy the web. A high pressure water hose also may be used to remove webs especially in hard to reach locations. Burning the web and caterpillars is hazardous and no more effective than the above technique. If you insist on this approach, use an oily rag attached to a pole or stick as a torch, being careful not to burn the tree limb and tender foliage. Avoid personal injury and ground fires from burning rag fragments by using a tin can as a rag holder. Caterpillars knocked from the tree or crawling on a patio may be killed by crushing. Use a broom to collect dead or crawling caterpillars around the home. Landowners with large forests of preferred host trees should spot check for eggs in several areas of the forest during the winter. If tent caterpillar eggs are abundant over large areas, chemical control measures should be planned for hatching time.

Several things should be considered before deciding to spray for tent caterpillars. Once feeding damage occurs it will remain throughout the season. If tent caterpillars have been allowed to feed and have completed their development, it is useless to spray. However, removal of the tent will eliminate the unsightliness of the tent itself. Tents are quite resistant to weather and will remain in the tree for long periods. If caterpillars are detected early, spray may be applied as spot treatments on webs. One carefully applied treatment, properly timed, is sufficient for control. Any of several insecticides can be used for controlling tent caterpillars. Not all insecticides are labeled for use on all host plants. To eliminate caterpillars as a nuisance around buildings use an aerosol spray containing synergized allethrins, synergized pyrethrins or tetramethrin.

                                                                     Saturniidae-Giant Silkworms.

The royal or regal moths and the giant silk moths belong to the family Saturniidae. Most members of this faintly are large moths, the cecropia being the largest moth in North America. Because of their large size and sometimes striking colors and shapes, they attract a lot of attention when they are encountered. Also because the moths are rarely abundant, they are hardly ever taken for granted when one announces its presence by fluttering against a window at night.

 The caterpillar stages of these moths are also large and spectacular and are observed more often than the moths. Some are ornamented with spines and barbed horns which makes them seem likely candidates for roles in horror movies. For the most part, this horrendous appearance is all show as far as harm to humans is concerned. However, the spines on the io moth caterpillar are true defensive weapons and can produce a painful sting to anyone who carelessly handles them.

 Most of the saturniid caterpillar species feed on a wide variety of trees and shrubs, but have a preference for certain plants. One or two of the larger types of caterpillars can cause severe defoliation. Hand picking these caterpillars is sufficient control, but wear gloves if it is an io. Some of the smaller species of royal moths caterpillars feed in colonies and do more damage than the less numerous larger types of caterpillars. For these caterpillars, as well as large caterpillars out of reach in a tree, insecticide sprays may be needed to prevent further tree damage.

 Cecropia Moth-Hyalophora cecropia. This is the largest of the North American moths with a wing spread of five to seven inches. Its overall color is various shades of brown, but there is a conspicuous white mark near the center of each wing. There is a dark eye spot and a tinge of lavender near the tip of the front wing. The moths make their seasonal appearance in early summer and lay their eggs. They are often found at lighted windows at night.  

The caterpillars take most of the summer to mature and are up to four inches long when fully developed. They are bluish green, and along the back there is a pair of yellow projections on each body segment. The first three pairs of tubercles are more conspicuous and are in the form of yellow balls with black spines. The Cecropia caterpillars feed mainly on cherry, plum, apple, elderberry, box elder, maple, birch and willow, but will also feed on linden, elm, sassafras and lilac. Rarely are they common enough to be considered a pest.

                                                                                      

                                       Cercopia moth larva.  Image courtesy (left) Michael Hodge and (right) Charles Benjamin Schwamb.

 Luna Moth-Actias luna . These moths are large, with a 4 to 5 inch wingspan. Wings are light green, marked with transparent spots and a pink-purple or yellow forewing margins and hind wings bearing long twisted tails. Antennae are feathery, with antennae of males being more feathery than those of females. Caterpillars are translucent light green with a pale yellow horizontal line along each side and reddish-orange fleshy knobs (tubercles) on each body segment. They grow to be 2 3/4 inches long.

There are a number of other common silk moths (Saturniidae). Luna moth caterpillars superficially resemble those of the polyphemus moth, Antheraea polyphemus (Cramer), but differ because they have vertical yellow lines on each segment rather than single horizontal lines along each side of the body.

Life Cycle: Adults begin to emerge in the spring (March) to mate and lay oval eggs. Caterpillars develop through several molts before spinning a papery cocoon among dead leaves that usually falls to the ground. There are two generations per year.

Habitat and Food Source(s): Caterpillars have chewing mouthparts. Adults have siphoning mouths. Caterpillars feed on leaves of walnut, hickory, sweetgum, maple, oak, persimmon, willow and other trees. Adults can be attracted to lights, or males can be attracted to an imprisoned female. All colors will fade in preserved specimens when exposed to light. Mated female luna moths can be caged over a food plant on which she will deposit eggs. Luna moths appear to be increasingly rare in east Texas.

Pest Status: "Moon" moths are active at night and are harmless.  Caterpillars feed on tree leaves but are rarely found in large numbers and are medically harmless without stinging hairs.

                                                                       

                                                                             Luna moth adult. Image courtesy Shawn Hanagran, Wikipedia

Sessidae-Clearwing Moths. The family of the clearwing moths unlike other Lepidoptera lacks the scales that cover the wings thus giving them the bright colors.  As their name implies their wings are transparent. The bodies are generally striped with yellow, sometimes very brightly, and they have simple antennae. The general appearance of many species is wasp or hornet-like. This enables them to be active in daylight. Worldwide there are 151 genera, 1370 species , and 50 subspecies. Most of these occur in the tropics, but there are many species in the United States. The larvae of the Sesiidae are typically wood-borers, or burrow in plant roots. Many species are serious pests of fruit-tree or timber cultivation, or crop plants.                                                                          

                                                                                              

                                                                                                                           A typical clearwinged moth.

                                                                                               Peach Tree Borer-Synanthrdon exitiosa

Identification. The adult Peachtree borer is a clear wing moth with a 1-1/4 wing span. Unlike the majority of moths, these fly during the day and are most active from 10 a.m. to 2 p.m. The female and male moths differ in appearance. The female is dark, steel blue with one or two wide orange bands around her abdomen. Her front wings are opaque while the hind ones are clear. The male moth is smaller and more slender. It is also steel blue, but has several narrow-yellow bands around the abdomen. Both pairs of wings are clear.

Damage. The Peachtree borer is a native North American pest that causes serious damage to peach, cherry, plum, nectarine, and apricot. Damage is caused by the larval stage, primarily to younger trees. Larvae tunnel into the roots and lower trunks of the hosts feeding on the growing tissue and inner bark. Young trees may be completely girdled and older trees may have their crop bearing capacity greatly reduced. Infested trees may yellow and eventually die as the larvae girdle the tree at the crown.

   Adult Peachtree Borers, male) bottom) and female (right)  

Life Cycle. Egg laying begins shortly after the moths emerge and lasts only a few days. The eggs are deposited on the trunk at or near the base. Females lay 500-600 eggs on average. The larvae will begin to hatch in 9 to 10 days. Upon hatching, the larvae wander down the trunk to the soil line and burrow into the bark, often entering through a crack or wound. When full grown, the larva is 1-1/4 in long, cream colored with a dark brown head. The winter is spent as a larva under the bark. In the spring the larva will construct a silken cocoon and cover it with tiny bits of chewed wood. The borer will remain in the pupal stage from 18 to 30 days before emerging as an adult. There is a single generation per year. Infestation by the Peachtree borer is often identified by oozing of gum around the base of the tree. The gum is usually mixed with dirt and reddish-brown frass. Frequently empty brown pupal cases can be found around the base of damaged trees, either at the head of the larval gallery or in the soil close to the tree trunk.

 Control. Control of peach tree borers in commercial orchards relies on preventing the larval establishment underneath the bark. Once under the bark, chemical control is ineffective. Insecticides should be timed to coincide with initial egg hatch in order to be effective. To aid in the timing of sprays, pheromone traps are used to alert producers to the presence and activity of Peachtree borer moths. Because egg hatch begins about 9 to 10 days after the moth’s emergence, insecticidal sprays should be applied 7 to 14 days after the first male Peachtree borer moths are captured in the traps.

Mating disruption relies on confusion to prevent peach tree borers from mating. Male peach tree borer moths normally locate female moths at night by following the sex attractant released into the air by the females. Mating disruption uses commercial dispensers of synthetic sex attractant to prevent male moths from locating females. Males are overwhelmed by the amount of pheromone and become desensitized to it. The result is that unfertilized moths are not able to lay viable eggs. Unlike other methods, peach tree borer moths are not killed with this technique. This technique is most successful in blocks of at least 5 acres and where initial populations of peach tree borer moth are low. There may be some damage along rows boarder woods or other areas that may be sources of already mated females. Keep in mind that mating disruption for peach tree borer will not control other insects that are normally controlled with cover sprays (plum curculio for example). Pheromone traps are used to ensure that the technique is working properly, as the male moths should not be able to locate the traps.

Before the development of chemicals for controlling peach tree borers, producers relied on digging the borers out of the bark by hand. This is still an alternative for backyard gardeners in the fall. Dirt should be removed from around the base of the tree to a depth of 4 to 5 inches. Care should be taken not to cut the sound bark more than necessary, and cutting should be done vertically. Carelessness may result in more damage to the tree than the damage that would have been caused by the borers! After the larvae have been located and removed, the dirt should be replaced around the base of the tree to the original level.

Sphingidae-Sphynx Moths. This family, (also commonly known as hawk moths and hornworms, includes about 1,200 worldwide species, most of which are tropical. They are moderate to large in size very fast flying moths. Their narrow wings lanced shaped wings and streamlined abdomen are clearly adaptations for rapid flight. Some hawk moths hover in midair while they feed on nectar from flowers and are sometimes mistaken for hummingbirds. Some of the sphingids are some of the fastest flying insects, capable of flying at over 50 km/h (30 miles per hour).

                                                                                                  Tomato Hornworm-Mandulca quiquemaculata

The tomato hornworm, Manduca quinquemaculata (Lepidoptera: Sphingidae), is native to the United States, and is commonly found throughout the northern states. This insect does not typically reach economically damaging levels on commercial farms. However, large numbers of larvae can sporadically occur in home gardens. Tomato hornworms feed only on solanaceous plants, most often on tomato. However, larvae will also attack eggplant, pepper, and potato. There are many solonaceous weeds that also serve as alternate hosts, including: horsenettle, jimsonweed and nightshade. There are usually 2 generations of this insect each year in western US.

Biology and Life Cycle. The adult moth, sometimes referred to as a "sphinx", "hawk", or "hummingbird" moth, is a large, heavy-bodied moth with narrow front wings. The moth is a mottled gray-brown color with yellow spots on the sides of the abdomen and a wing spread of 4 to 5 inches. The hindwings have alternating light and dark bands. Eggs of the tomato hornworm are deposited singly on both the lower and upper surface of leaves in late spring. The eggs hatch in six to eight days and are oval, smooth, light green to yellow in color, and measure 0.10 cm in diameter. Larvae are pale green with white and black markings (see photo), and undergo 5-6 instars. The first instar is yellow to white in color with no markings. Later instars develop eight white, lateral "V-shaped" marks. A black projection or "horn" on the last abdominal segment gives the caterpillar the name "hornworm." The caterpillar reaches the final instar in 3-4 weeks, and is 3 1/2 to 4 inches when fully mature. Fully-grown larvae then drop off of the plants and burrow into the soil to pupate. During the summer months, moths will emerge from pupae in about 2 weeks. Moths emerge from the soil, mate, and then begin to deposit the eggs of the next generation on tomato plants. By early fall, the pupae will remain in the soil all winter and emerge as a moth the following spring.

 

                                                                                                                                                                                  

                                                                                                                                                                                              

                                                                                 Larva and adult of Tomato Hornworm.  Image Courtesy Shawn Hanrahan at the Texas A&M University                                                                                                                                                                                                                                            

Damage. The larva is the damaging stage and feeds initially on the upper portions of leaves, leaving behind dark green or black droppings. The larvae blend in with the plant canopy, and therefore go unnoticed until most of the damage is done. Late instar larvae are capable of destroying several leaves as well as the fruit. As the larvae mature in size the amount of defoliation increases, with the last instar consuming over 90% of the total combined foliage consumed by all instars.

Control. Handpicking the hornworms from infested plants is a safe and effective option in smaller plantings. Roto-tilling the soil after harvest will destroy many of the burrowing larvae which are attempting to pupate. Tillage has shown to cause up to 90% mortality. There are many natural factors that help to control tomato hornworm infestations. The egg stage and early instar larvae are often preyed upon by various general predatory insects such as lady beetles and green lacewings. Tomato hornworm larvae are also parasitized by a number of insects. One of the most common is a small braconid wasp, Cotesia congregatus. Larvae that hatch from wasp eggs laid on the hornworm feed on the inside of the hornworm until the wasp is ready to pupate. The cocoons appear as white projections protruding from the hornworms body (see photo, left). If such projections are observed, the hornworms should be left in the garden to conserve the beneficial parasitoids. The wasps will kill the hornworms when they emerge from the cocoons and will seek out other hornworms to parasitize. Another important natural enemy is the wasp, Polistes spp. (Hymenoptera: Vespidae). This common wasp kills and feeds upon a large proportion of the larvae, and will also attack cabbage looper and other garden caterpillars.

Tobacco Hornworms-Mandulca sex

Identification. The tobacco hornworm, it is closely related to and often confused with the very similar tomato hornworm (Manduca quinquemaculata); the larvae of both feed on the foliage of various plants from the family Solanaceae. The tobacco hornworm can be distinguished by its seven diagonal lines on its sides; tomato hornworms have eight V-shaped marking. An easy way to remember the markings is tobacco hornworms have straight white lines like cigarettes, while tomato hornworms have V-shaped markings as in V8 juice.                                                                                                                                                                                                                                                                          Tobacco Hornworm larva and adult. Right image courtesy Shawn Hanrahan at the Texas A&M University Life cycle. M. sexta has a short life cycle, lasting about 30 to 50 days. In most areas, M. sexta have about two generations per year, but they can have about three or four generations per year in California. M. sexta eggs are spherical, approximately 1 millimeter in diameter, and translucent green in color. They typically hatch 2–4 days after they are laid. Eggs are normally found on the underside of foliage, but can also be found on the upper surface. M. sexta caterpillars feed on plants of the family Solanaceae, principally tobacco and members of the Datura family of plants. Near the end of this stage, the caterpillar seeks a location for pupation, burrows underground, and pupates. The searching behavior is known as "wandering." The instinct of wandering can be visually confirmed by spotting the heart (aorta) which is a long, pulsating vein running along the length of the caterpillar's dorsal side. The heart appears just as the caterpillar is reaching the end of the final instar.  M. sexta has five larval instars which are separated by ecdysis (molting), but may add larval instars when nutrient conditions are poor. The pupal stage lasts approximately 18 days under laboratory conditions (17 hours light, 7 hours dark, 27°C). When reared on a short-day photoperiod (12 hours light, 12 hours dark), pupae enter a state of diapause that can last several months. During the pupal stage, structures of the adult moth form within the pupal case which is shed during eclosion (adult emergence).  M. sexta has mechanisms for selectively sequestering and secreting the neurotoxin nicotine present in tobacco. M. sexta is a common model organism, especially in neurobiology, due to its easily accessible nervous system and short life cycle. It is used in a variety of biomedical and biological scientific experiments. It can be easily raised on a wheat-germ based diet. The larva is large and thus relatively easy to dissect and isolate organs from. White Lined Sphynx Moth-Hlyes lineate.  Upper side of forewing is dark olive brown with paler brown along the costa and outer margin, a narrow or sometimes lime green and black. Many individuals have a subdorsal stripe. The head, prothoracic shield, and the anal plate are one color either green or orange with small black dots. The horn varies from either yellow or orange and sometimes has a black tip.                                                                      White lined sphinx moth adult and larvae.  Larval image courtesy of Inzelbeth. Life History. Adults usually fly at dusk, during the night, and at dawn, but they will also fly during the day. Caterpillars pupate in shallow burrows in the ground. Massive population buildups occur which stimulate emigrations to colonize more northern areas. These flights typically occur twice during the year from February-November.  Adults feed on nectar from a variety of flowers including columbines, larkspurs, petunia, honeysuckle, moonvine, bouncing bet, lilac, clovers, thistles, and Jimpson weed. They occur in a wide variety of habitats including deserts, suburbs, and gardens. This moth ranges from Central America north through Mexico and the West Indies to most of the United States and southern Canada. Also occurs in Eurasia and Africa. Damage. Caterpillar hosts include a great diversity of plants including willow weed (Epilobium), four o'clock (Mirabilis), apple (Malus), evening primrose (Oenothera), elm (Ulmus), grape (Vitis), tomato (Lycopersicon), purslane (Portulaca), and Fuschia with  Occasional outbreaks of caterpillars have damaged tomatoes, grapes, and garden crops.                                                                                Geometridae-Inchworms or Spanworms. Identification. Adults typically have slender bodies and relatively large, broad forewings, often crossed by thin wavy or zig-zag lines; females of some species are wingless or have flightless atrophied wings.  When at rest, many geometrid moths hold their wings away from the body and flat against the substrate (in contrast to most noctuid moths, which tend to fold their wings over their abdomen).  Some species hold their wings in a characteristic position such as: flat & at right-angles to the body, or inclined 45 degrees above horizontal, or vertically over their back like a butterfly. The larvae generally have only two pairs of prolegs (on sixth abdominal segment and last abdominal segment)) rather than the usual five pairs in most Lepidoptera.  The lack of prolegs in the middle of the body (a pair on abdominal segment 3 to 6) necessitates the characteristic method of locomotion, functionally drawing the last abdominal segment up to the thoracic legs to form a loop, and then releasing the thoracic thus extending the body forward.                                                                                                                                                                         Typical Inchworm adult. Image courtesy of Gerald Dewey, USDA Forest Service, Bugwood.  Right. Typical inchworm larvae.  Image courtesy of Chris Maier, Connecticut Ag. Experiment Station Archives, Bugwood.                                                                                                            Fall Cankerworm, Alsophila pomelaria Identification. Mature larvae are about 25 mm long and can vary between light green and dark brownish-green. The light green caterpillars have white lines running down their body from the head to the tip of the abdomen. The dark brownish-green caterpillars have a black stripe the length of their back. When more dark colored caterpillars are seen, it may be a sign of a heavy infestation. Larvae have two pairs of legs on their thorax and three pairs of prolegs on their abdomen. The first pair of prolegs, when looking back from the head, is much smaller than the last pair. The pupa can be found just beneath the surface of the ground and is wrapped in a silken cocoon. The male moths have a 25-35 mm wingspread with brown glossy forewings crossed with irregular white bands. The females are brownish-gray, wingless, and 10-12 mm long. Eggs resemble a vase and are less that 1 mm in diameter. They are dark grayish-brown with a dot and a ring on top.                                                                                                                                                                                               Fall canker worm male.  Image courtesy USDA Forest Service. Life History. This pest exhibits one generation per year. Larvae hatch in the spring that occurs the same time as leaves begin to emerge from the buds on host trees. During a major infestation, larvae can eat the leaves as fast as they grow. Larvae reach maturity in 5 to 6 weeks after hatching. Once mature, larvae lower themselves from the tree canopy on a silken thread. Once on the ground, they spin a cocoon made of silk and soil particles. The pupal stage is inside this cocoon. This species will remain in this stage until freezing temperatures occur from late October to early December. The wingless female simply climbs the nearest tree and mates with the male. Once mated, females lay about 100 eggs in compact rows in a single layer on smaller twigs.  The fall cankerworm is a common native pest of hardwood trees in North America. Common trees that this species prefers to feed on are ash, basswood, beech, black cherry, red maple, sugar maple, red oak, and white oak. It will also feed on the leaves of apple, birch, boxelder, dogwood, elm, hickory, and many other hardwoods. This pest gets its name because adults are active in late fall even though larvae feed in the spring. There is also a spring cankerworm, however, the adult stage of this species is active in early spring, and this insect is not as common as the fall cankerworm. Nearly every year, the fall cankerworm causes at least some small areas of defoliation in the forest. Damage. Young larvae begin feeding on the area in between small veins on the leaf. However, once larvae are mature, they consume the leaf entirely leaving only the midrib and major veins. This pest often defoliates an entire tree. If defoliation occurs two years in a row, the tree can die, especially if it has been stressed by drought or poor site conditions. Outbreaks normally occur for a period of one to two years. Infestations can be a nuisance in public use areas, especially when the mature larvae are silking out of the tree. On windy days larvae can be blown onto people beneath the infested trees. Management. Monitoring for this species should begin in early May when young larvae have started feeding. If there is a significant population, a registered insecticide may be applied according to label directions when small larvae are feeding. Weather is also a factor in regulating this pest. Cool, wet spring weather has an adverse effect on its populations. There are also some natural enemies of this species. One is the tiny wasp, Telenomus alsophilae that is an egg parasitoid. Another is the ground beetle, Calosoma frigidum, that feeds on larvae. On shade trees it is possible to place a sticky band around the trunk in late fall in order to capture females before they lay their eggs. This method, however, does not always work, especially if there are unbanded infested trees nearby.       Wingless female fall cankerworm. Image courtesy John Dhent, USDA Forest Service. Right. Larvae of fall cankerworm. Image        courtesy of Chris Maier, Connecticut Agriculture Extension Archives. Arctiidae-Tiger Moths. This is a large and diverse family of moths with around 11,000 worldwide species This family includes the groups commonly known as tiger moths (or tigers), which usually have bright colors, footmen, lichen moths and wasp moths. Many species have 'hairy' caterpillars which are popularly known as woolly bears or woolly worms. A characteristic of the family is a tympanum on the thorax which when vibrated to produce ultrasonic sounds. These sounds are used in mating and for defense against predator. Many species retain distasteful or poisonous chemicals acquired from their host plants. Larvae typically acquire these chemicals which may be passed onto molting adults. In some species adults can also acquire these toxicants by regurgitating on decomposing plants containing the compounds, and sucking up the fluid. Female adults can transfer the toxicants to their eggs, or the males sometimes transfer them to females to help with defense of the eggs.  Some larvae possess urticating or stinging hairs. The insects advertise these defenses with bright coloration, unusual postures, odors, or, in adults, ultrasonic vibrations. Some species mimic other moths that are poisonous, or wasps that sting. The ultrasound signals help nocturnal predators to learn to avoid the moths. Many of the caterpillars and adults are active during the daytime. If disturbed, woolly bear caterpillars will roll into a tight spiral  Local folklore of the American Northeast holds that that "wooly bears" have the ability to predict the weather, similar to that of the Groundhog. The forthcoming severity of a winter may be indicated by the amount of black on the Isabella tiger moth's caterpillar, the most familiar woolly bear in North America; more brown than black means a fair winter, but more black than brown means a harsh winter.  However, the relative width of the black band varies among instars, not according to weather. The mythical qualities attributed to woolly bears in the American Northeast have led to such things as the Woolly Bear Festival.                                                                                           Isabella Tiger Moth.  Image courtesy of Ironchris.   Salt Marsh Moth or Acrea Moth-Estigmene acrea. This species is common throughout most of North America. The head and thorax are white with the abdomen being yellow-orange with a row of black spots. The fore wing is white with a variable amount of black spots (some individuals lack these spots). The hind wing is yellow-orange in males and white in females. Both sexes have 3-4 black spots or blotches on their hind wings. The wingspan measures 1 to slightly over 2 inches.                                                                              Salt Marsh Caterpillar Adult, Egg Mass and Larva.  Images left to right courtesy of Megam Mccarthy, Whitney Cranshaw-Colorado State University                                                                                     and lton N. Sparks, Jr., University of Georgia, Bugwood.org Life Cycle-Behavior.  This moth may be seen from May to August but remains active throughout the year is warmer areas of its range. The yellowish eggs are laid in clusters on the host plant leaves. The larva, known as the Salt Marsh Caterpillar, is highly variable in color and ranges from pale yellow to dark brownish-black. It has numerous soft setae which are longer towards the end of the body. The thoracic and abdominal segments have a few rows of either orange or black warts. The pupa hibernates in a cocoon.  A generation can be completed in 35 to 40 days under ideal conditions, but most reports from the field suggest about six weeks between generations. The number of generations per year is estimated at one in the northern states to three to four in the south. Overwintering reportedly occurs in the mature larval stage, with pupation early in the spring. Salt marsh caterpillars usually are infrequent early in the season, but may attain high numbers by autumn. Larvae are active dispersers, a habit that is relatively uncommon among caterpillars. Most commonly, late instar larvae are found individually or in large numbers ambling over the soil, searching for suitable food. Damage to margins of crop fields often occurs as such larvae desert drying weeds for irrigated crops.  Reportedly young larvae drop readily from plants when disturbed, spin a strand of silk, and are blown considerable distances by wind. Frequency of distribution by wind is unknown. Saltmarsh caterpillar's peculiar common name is derived from initial description as a pest of salt-grass hay grown in the vicinity of Boston. This is an anomaly, and despite the wide host range of this insect, grasses are not particularly preferred. Broadleaf weeds are the normal host plants, but larvae commonly disperse from these late in the growing season to damage vegetable and field crops. Vegetables injured include asparagus, bean, beet, cabbage, carrot, celery, corn, lettuce, onion, pea, tomato, turnip, and probably others. Field crops damaged are alfalfa, clover, cotton, soybean, sugarbeet, and tobacco. The favored weed host seems to be pigweed, Amaranthus spp., but many others may be consumed, including anglepod, Gonolobus sp.; sicklepod, Cassia tora; dog fennel, Eupatorium capillifolium; ground cherry, Physalis spp.; and mallow, Anoda sp. Young larvae feed gregarously and skeletonize foliage. Older larvae are solitary and eat large holes in leaf tissue. Older larvae may disperse long distances in search of food, sometimes moving in large numbers. Commonly this is associated with maturation of cotton or weeds in the autumn. Thus, these caterpillars tend to be damaging to fall-planted crops. Foliage consumption at least doubles with each succeeding instar, and mature larvae can consume over 13 sq cm of thick-leaved foliage, such as sugarbeet, daily. It is estimated estimated that one to 1.5 mature caterpillars per plant could inflict 20% defoliation to a bean plant, a level adequate to cause yield loss. Control. Saltmarsh caterpillar larvae frequently are parasitized, particularly by tachinids (Diptera: Tachinidae). In Arizona, the most common parasitoids were Exorista mellea(Walker) and Leschenaultia adusta (Loew), but Gymnocarcelia ricinorum Townsend and Lespesia archippivora (Riley) were also observed (Taylor 1954). Jackson et al. (1970) documented the biology and importance of L. adusta. Arnaud (1978) reports additional species of tachinids associated with saltmarsh caterpillar. Hymenopteran parasitoids are known from both the larval and egg stages, and include Apanteles diacrisiae Gahan (Braconidae); Therion fuscipenne (Norton), T. morio (Fabricius), Casinaria genuina (Norton), Hyposoter rivalis (Cresson) (all Ichneumonidae); Psychophagus omnivorus (Walker), Tritneptis hemerocampae Vierick (both Pteromalidae); Anastatus reduvii (Howard) (Eupelmidae); and Trichogramma semifumatum(Perkins) (Trichogrammatidae). General predators such as lady beetles (Coleoptera: Coccinellidae), softwinged flower beetles (Coleoptera: Melydridae), and assassin bugs (Hemiptera: Reduviidae) prey on these caterpillars, but are not thought to be very important in population regulation. Insecticides are commonly used to suppress saltmarsh caterpillars if they become abundant in vegetable crops. Baits are not effective. Most damage occurs at field margins as larvae disperse into crops from nearby senescent vegetation. Both chemical insecticides and Bacillus thuringiensis are recommended. Physical barriers, including ditches or trenches with steep sides, can be used to interrupt invasion of crops by caterpillars. Woolybear Caterpillar- Pyrrharctia Isabella. Although not a pest species the larva of this moth has attracted considerable attention due to its unique coloration. There are a number of festivals around the country that celebrate this moth for example in Banner Elk north Carolina there is a 30 plus year festival that  includes booths with crafts, food, and races. The winning Woolly Worm predicts the winter weather for the following winter. It is believed that if a woolly bear caterpillar's brown stripe is thick, the winter weather will be mild and if the brown stripes are narrow, the winter will be severe. Identification. The adult is known as the Isabella tiger moth and the larva is called the banded woolly bear. This species is black at both ends with a band of coppery red in the middle. The adult moth is dull yellow to orange with a robust, furry thorax and small head. Its wings have sparse black spotting and the proximal segments on its first pair of legs are bright reddish-orange. Adult banded wollybear caterpillar.  Image courtesy of Steve Juvetson.  Larvae of banded wollubear caterpillar image courtesy Whitney Cranshaw, Colorado State University, Bugwood The banded woolly bear larva emerges from the egg in the fall and overwinters in its caterpillar form. It survives winter freezes by producing a cryoprotectant in its tissues. Once the weather warms, the larva devours all the grass and weeds it can, pupates, and becomes an adult, which then lives through the summer. It is the larvae of this species which are the subject of common folklore, which has it that the forthcoming severity of a winter can be predicted by the amount of black on the caterpillar; this is the most familiar woolly bear in North America. But in fact, larvae produced in the same clutch of eggs can vary from mostly red to mostly black, even when reared under the same conditions, and this variability invalidates any actual temperature-related trends that may otherwise be evident. In fact, the orange band will grow towards the ends of the body, with the black bands decreasing in size, as the larva matures. The setae of the woolly bear caterpillar do not inject venom and are not urticanting—they do not cause irritation, injury, inflammation, or swelling However, they will play dead if picked up or disturbed. Handling them is discouraged, however, as the bristles may cause dermatitis in people with sensitive skin. Recent research has shown that the Woolly Bear caterpillar may eat alkaloid-laden leaves to help fight off parasitic fly larva that can be laid inside their abdomens. This research showed what is called "the first clear demonstration of self-medication among insects". Fall Webworm-Hyphantria cunea. This is common native caterpillar occurring throughout the United States and southern Canada. The larvae feed in mass on leaves of hardwood trees while surround by webbing. Typically the webs are located at the outer ends of branches; however, when webworm populations are high, webbing is more extensive and may envelope the entire crown of the tree. The webworm is capable of defoliating and causing damage to forest trees, but it is most important as a pest of shade and ornamental trees in urban and suburban areas. Identification. Fall webworm adults are small to medium-size moths with wingspan of 1 to 1½ inches. Moth adults are pure white or white with forewings dotted with small dark spots. The spotted-forewing characteristic is associated primarily with race and sex, and possibly with region. The larvae can be identified readily to race by color. Orange-race caterpillars have reddish heads and orange tubercles in rows along the body. Bodies are tan throughout most of the developmental period but become darker in the last stage. Larvae of the black race have black heads and tubercles; body color is light greenish white. Caterpillars of both races are densely clothed with hairs that arise in clumps from tubercles. Full-grown webworm larvae are 1 to 1¼ inches long. Many species of forest, shade, ornamental, and fruit trees are listed as hosts of the fall webworm. Hosts are almost wholly hardwoods including pecan, persimmon, cherries, and sourwood, sweetgum, willow, and mulberry, elderberry, hickories, sycamore, blackgum, elm, redbud, and baldcypress. Trees listed above are considered to be primary hosts of the fall webworm, i.e., trees where eggs are deposited and where larval development is usually completed. In several instances, however, larvae have been observed to feed and develop on foliage of other plants intermixed with primary hosts. For example, larvae from eggs laid on red mulberry fed first on mulberry, then leaves of common greenbriar climbing the mulberry stem, and subsequently completed development on wild rhododendron interconnected to mulberry by greenbriar. Life Cycle and Habits. They overwinter as pupae in cocoons among leaves and trash on the ground or in the upper layer of soil. Adults emerge in spring. Females lay their eggs in groups of 300 to over 1000 on foliage of host trees. The eggs may be deposited in a single or double layer on either of the leaf. Once hatched the larvae feed in colonies with webbing of foliage beginning with onset of feeding. Feeding by early stage caterpillars is usually confined to one surface of the leaf, but as larvae develop, both surfaces are consumed leaving only a network of leaf veins. Webs are enlarged to enclose additional leaves as webworms feed and grow. Duration of the larval stage is usually four to six weeks. Fall webworm populations vary greatly over the years. Typically, populations are low or "normal" in most years; webs are few and generally scattered among a few of the most common host trees. Periodically, however, "outbreak" populations occur; webs become numerous; a greater number of species of trees become infested; and the increase in webbing and loss of foliage attract attention and cause concern (one such outbreak occurred in some areas of the state in 1997). Outbreaks usually last one or two years then populations subside to "normal" levels. In the south, webworm activity begins in April and may continue into October with two generations per year. Outbreak populations of fall webworm can completely defoliate host trees. Healthy hardwoods usually survive and recover without permanent injury. However, several consecutive defoliations can cause dieback in the crown, and may contribute to the death of weak, declining trees. The webworm is not usually a serious pest in natural forest stands. Infestations are of greatest concern on shade, ornamental, and urban forest trees. Here, loss of foliage and unsightly webs seriously reduce the aesthetic and environmental values of the trees. In this circumstance, control of the webworm may be desirable. Control recommendations are available from appropriate Extension Service personnel. Control. The fall webworm has many natural enemies, i.e., predators, parasites, and disease. These play an important part in maintaining webworm populations at low levels during many years. Included are birds and predaceous and parasitic insects. Common insect enemies encountered in populations are parasitic wasps and assassin bugs.

Larvae, webbing and adult of fall webworm.  Left and middle images courtesy Whitney Cranshaw, Colorado State Univ., Bugwood. Right. H C Ellis, University of Georgia, Bugewood.

                                                                                        Noctuidae-Loopers-Underwings.

 This is the largest family of Lepidoptera.  It follows that it also contains the largest number of pest species in this order.  Most adults are medium sized with dull coloration.  The name underwings refer to the fact that the second pair of wings is typically distinctly different in color than the first.

                                                                                   Cabbage loopers-Trichoplusia ni  

The cabbage looper is found throughout Canada, Mexico, and the United States wherever crucifers are cultivated, and on any other continents. However, overwintering in the United States apparently occurs only in the southernmost states. It is somewhat erratic in occurrence, typically very abundant one year and then scarce for two to three years. This is likely due to a nuclear polyhedrosis virus which can be devastating to populations. The cabbage looper is highly dispersive, and adults have sometimes found at high altitudes and far from shore. Flight ranges of approximately 200 km have been estimated.

Description. Cabbage looper eggs are hemispherical in shape, with the flat side affixed to foliage. They are deposited singly on either the upper or lower surface of the leaf, although clusters of six to seven eggs are not uncommon. Young larvae initially are dusky white, but become pale green as they commence feeding on foliage. Larvae possess three pairs of prologs which are located on abdominal segment 5 6 and 10. Prolegs are fleshy non-segmented legs that characteristic of all Lepidopteras larvae. They are frequently referred to as semi-loopers since they crawl by arching their back to form a loop and then projecting the front section of the body forward. The mature larva is predominantly green, but is usually marked with a distinct white stripe on each side. The thoracic legs and head capsule are usually pale green or brown. Dorsally, the larva bears several narrow, faint white stripes clustered into two broad white bands. In some cases the mature larva is entirely green. The body is narrower at the anterior end, and broadens toward the posterior. It measures 3 to 4 cm in length at maturity. Cabbage looper is easily confused with other loopers, but can be distinguished from most by the presence of small, nipple-like structures (vestigial prolegs) located ventrally on abdominal segments 3 and 4.

The forewings of the cabbage looper moth are mottled gray-brown in color; the hind wings are light brown at the base, with the distal portions dark brown. The forewing bears silvery white spots centrally: a U-shaped mark and a circle of dots that are often connected. The forewing spots, although slightly variable, serve to distinguish cabbage looper from most other crop-feeding noctuid moths. The moths have a wingspan a little over an inch.

Life Cycle. The number of generations completed per year varies from two to three in Canada, five in North Carolina, to five to seven in California. The generations overlap considerably, and therefore are indistinct. Development time (egg to adult) requires 18 to 25 days depending on temperature. Cabbage loopers do not diapauses and consequently do not tolerate low temperatures. However due to its strong dispersal behaviors it reinvades most of the United States and all of Canada annually after overwintering in southern latitudes. The lower limit for development is about 10 to 12°C, and 40ºC is fatal to some stage. At pupation, a white, thin, fragile cocoon in formed on the underside of foliage, in plant debris, or among clods of soil. The pupa contained within is initially green, but soon turns dark brown or black. The pupa measures about 2 cm in length. Duration of the pupal stage is about four, six, and 13 days at 32, 27, and 20°C, respectively.

Females lay 300 to 600 eggs. During the adult stage, which averages 10 to 12 days, 300 to 600 eggs are produced by females \ Moths are considered to be seminocturnal because feeding and oviposition sometimes occurs about dusk. They may become active on cloudy days or during cool weather, but are even more active during the nighttime hours. They oviposit readily at temperatures as low as 15.6°C, but flight activity is higher on warmer evenings.

Host Plants and Damage. The cabbage looper feeds on a wide variety of cultivated plants and weeds. As the common name implies, it feeds readily on crucifers, and has been reported damaging broccoli, cabbage, cauliflower, Chinese cabbage, collards, kale, mustard, radish, rutabaga, turnip, and watercress. Other vegetable crops injured include beet, cantaloupe, celery, cucumber, lima bean, lettuce, parsnip, pea, pepper, potato, snap bean, spinach, squash, sweet potato, tomato, and watermelon. Additional hosts are flower crops such as chrysanthemum, hollyhock, snapdragon, and sweetpea, and field crops such as cotton and tobacco. Surprisingly few common agricultural weeds are frequent hosts; among those that are suitable are lambs quarters, wild lettuce, dandelion and curly dock.

Cabbage loopers are leaf feeders, and in the first three instars they confine their feeding to the lower leaf surface, leaving the upper surface intact. The fourth and fifth instars chew large holes, and usually do not feed at the leaf margin. In the case of cabbage, however, they feed not only on the wrapper leaves, but also may bore into the developing head.  Feeding sites are marked by large accumulations of sticky, wet fecal material. Despite their voracious appetite, larvae are not always as destructive as presumed.

Natural Enemies. The cabbage looper is attacked by numerous natural enemies, and the effectiveness of each seems to vary greatly. Most studies note the effectiveness of wasp and tachinid parasitoids, and a nuclear polyhedrosis virus (NPV). Predation has not been well studied except in cotton. The Trichoplusia ni NPV is well studied. Larvae normally die within five to seven days of consuming virus inclusion bodies. Early signs of larval infection are a faint mottling of the abdomen in the area of the third to the sixth abdominal segments. This is followed by a more generalized blotchy appearance, and the caterpillar eventually becomes creamy white in color, swollen, and limp. Death usually follows within hours following the limp condition, and caterpillars are often found hanging by their prolegs. Dark blotches appear after death, and the integument becomes very fragile and eventually ruptures. The body contents, heavily contaminated with new inclusion bodies, then drip onto foliage where they can be consumed by other larvae.

Microbial insecticides currently play a role in cabbage looper management, and their potential role has yet to be fully realized. Bacillus thuringiensis has long been used for effective suppression of cabbage looper, and has the advantage of not disrupting populations of beneficial insects. T. ni NPV is effective, but has not been commercialized because of the narrow host range. Home gardeners sometimes collect loopers dying of T. ni NPV, grind up the larval cadavers, and concoct their own effective microbial control agent. Mass release of Trichogramma spp. has been investigated for cabbage looper suppression. Looper egg parasitism can be increased several fold by careful timing of parasitoid release. Effectiveness varies among crops, however. This approach was most suitable in tomato, but also effective in crucifers and pepper.

                                                                      

                                                     

                Adult and Larval cabbage looper.   Left image courtesy of Calibas. Right image courtesy of Alton N. Sparks, Jr., University of Georgia, United States.

Alfalfa Looper-Autographa californ Adults have silvery-gray forewings marked with an ivory colored funnel-shaped mark resembling that found on the forewings of cabbage looper. Alfalfa loopers are larger than cabbage loopers and have a wingspan of 30 to 40 mm. Larvae are about 25 mm long and closely resemble the cabbage looper in color, but usually have a dark top stripe edged with white lines and two obscure white top-lateral lines. Larvae have three pairs of legs on the thorax and three pairs of prolegs on the abdomen (one pair on segments five and six and one pair on the terminal segment). Eggs are round, white to cream colored, and are laid singly on undersides of leaves.

                                                                                                            

                                    Larvae and Adult of Allalfa Looper.  Image Courtesy Peggy Greb, USDA Agricultural Research Service, United States

Identification. Distribution and Life History.

This pest is distributed throughout the United States and parts of Canada. Alfalfa loopers overwinter as pupae either in soil or in trash near the base of host plants. Moths begin emerging in late April and May and adults lay eggs singly on weed hosts (mostly wild crucifers). Eggs hatch in three to five days and larvae feed for about two weeks before pupating in cocoons on the host plant or in trash. The total development time from egg to egg requires about 30 days. Adults emerge in about seven days, mate, and females deposit eggs as before about three days after emerging. Damage is most evident in June and July and again in September and October. There are three or four generations each year.

 

Damage. The alfalfa looper is more widespread and destructive than the cabbage or celery looper. The larvae feed on leaves causing ragged-edged holes in the leaf and on

the leaf margins. The major damage caused by larvae and pupae is contamination of the heads of cole crops and processed foods, and defoliation of peas, sugar beets, alfalfa, beans, mint, and spinach.

 

Control. As with cabbage loopers its population is often reduced by a virus disease and several predators and parasites, but the population of natural enemies may not be sufficient to reduce heavy infestations. Insecticides may be used to prevent damage by this pest, but fields should be sampled prior to treatment to establish the need for treatment. Insecticides are much more effective against small larvae. Bacillus thruingiensis kurstaki (Btk) has been used successfully to reduce looper populations in some crops, but multiple applications and careful timing is necessary for successful control.

 

Beet Armyworm-Spodoptera exuiga.  Moths are medium sized with a wingspan of 25-30 mm. The forewings are a mottled gray and brown with irregular banding and a light colored bean-shaped spot near the center. The hind wings are a more uniform white or dirty white with a dark line near the margin. Eggs are laid in clusters of 50-150, greenish to white and are covered with a layer of whitish scales that give the egg mass a fuzzy or cottony appearance. Larvae are pale green to yellow during the first two instars. Larger larvae vary in appearance. Large larvae tend to be green to dark green dorsally and may have a series of dashes that give the appearance of longitudinal lines on the back. Large larvae generally have a dark line along the side of the body with a light line below the dark line. The underside of large larvae are generally pink or yellow. On the second segment behind the head, there is a small black spot on each side of the body. This spot usually becomes visible to the field observer when the caterpillar reaches about 1/3 of an inch. The spot may be difficult to see on a dark caterpillar. Squeezing the caterpillar from the rear may make the spot more apparent. Larvae range from less than 1/10 of an inch when newly emerged to about 1 inch when fully grown.

                                                                                  

                                                          Beet armyworm larvae.  Image courtesy Frank Peairs, Colorado State University, United States

Life Cycle. Egg clusters are usually deposited on the underside of leaves. Females normally deposit 300-600 eggs during their lifetime. Eggs hatch in 2-3 days during warm weather. Early instar larvae are gregarious, feeding as a group and skeletonizing leaves. Larvae are primarily foliage feeders during the first two instars which require about 4 days. Third instar larvae disperse and will attack fruit but can complete development on foliage in the absence of fruit. Normally, larvae develop through 5 instars in 9-10 days. Larvae reach a maximum size of about 22.5 mm. Pupation occurs in the soil and the pupal stage generally lasts 6-7 days. Total generation time is about three weeks.

Damage. The beet armyworm commonly feeds on asparagus, cotton, corn, soybean, tobacco, alfalfa, table and sugar beets, pepper, tomato, potato, onion, pea, sunflower and citrus. Plantain, lambs quarters and redroot pigweed are important wild hosts. While the potential for significant infestations is more likely in the fall, this pest can be a problem in the spring production season as well. This pest has generally been considered a secondary pest, with significant infestations usually occurring only after repeated use of broad spectrum insecticides which decimate its parasites and have little impact on the beet armyworm because of resistance to most older insecticide chemistries. However, in recent years this pest has frequently established in fields prior to heavy insecticide use.

The first two instars larvae are gregarious and feed in groups on foliage, typically damaging young terminal growth. The clumped skeletonizing of foliage is known as a beet armyworm 'hit' in many crops. Profuse silk webbing may give infested plants a shiny appearance. Later instars feed on foliage and other plant parts; no webbing is produced. Third and later instar larvae disperse and may continue feeding on foliage but will readily bore into fruit.

Control. Beet armyworm moths can be monitored with pheromone traps, but adult abundance does not always correlate with subsequent larval problems. Scouting for beet armyworms generally involves inspection of foliage for egg masses, larvae, and 'hits.' Egg masses can be difficult to locate because of their clumped nature. In fruiting vegetables, insecticide applications based on the detection of 'hits' generally provides ample protection as the early instars do not attack fruit and 'hits' can be detected prior to fruit loss. The lowest level of beet armyworm that can be tolerated without significant yield loss is an average of 1 larvae per 20 plants. Beet armyworm should be managed to keep the larval population from exceeding this level in the field.

                                                                             Fall Armyworm-Spodoptera frugipera

                                                                                                                                                                                                                                         

Fall armyworm larva. Left Image courtesy Clemson University,USDA Cooperative Extension Slide Series, Bugwood.org. The fall armyworm is native to the tropical regions of the western hemisphere from the United States to Argentina. The fall armyworm is a strong flier, and disperses long distances annually during the summer months. It is recorded from virtually all states east of the Rocky Mountains. However, as a regular and serious pest, its range tends to be mostly the southern states.

Description. Young larvae are greenish with a black head, the head turning light orange in the second instar. In the second, but particularly the third instar, the dorsal surface of the body becomes brown, and lateral white lines begin to form. In the fourth to the sixth instars the head is reddish brown, mottled with white, and the brownish body bears white subdorsal and lateral lines. Elevated spots occur dorsally on the body; they are usually dark in color, and bear spines. The face of the mature larva is also marked with a white inverted "Y" and the epidermis of the larva is rough or granular in texture.

The moths have a wingspan of 32 to 40 mm. In the male moth, the forewing generally is shaded gray and brown, with triangular white spots at the tip and near the center of the wing. The forewings of females are less distinctly marked, ranging from a uniform grayish brown to a fine mottling of gray and brown. The hind wing is iridescent silver-white with a narrow dark border in both sexes.

Life Cycle . The life cycle is completed in about 30 days during the summer, but 60 days in the spring and autumn, and 80 to 90 days during the winter. The number of generations occurring in an area varies with the appearance of the dispersing adults. Since they do not diapauses in the colder areas of the US they do not appear until early fall and consequently only exhibit 1 generation per year. The number of generations per year in warmer area will vary from 2 to 4.In coastal areas of north Florida, moths are abundant from April to December, but some are found even during the winter months.

The egg is dome shaped; the base is flattened and the egg curves upward to a broadly rounded point at the apex. The number of eggs per mass varies considerably but is often 100 to 200, and total egg production per female averages about 1500 with a maximum of over 2000. The eggs are sometimes deposited in layers, but most eggs are spread over a single layer attached to foliage. The female also deposits a layer of grayish scales between the eggs and over the egg mass, imparting a furry or moldy appearance. Duration of the egg stage is only two to three days during the summer months. Duration of the larval stage tends to be about 14 days during the summer and 30 days during cool weather

Pupation normally takes place in the soil, at a depth 2 to 8 cm. The larva constructs a loose cocoon, oval in shape and 20 to 30 mm in length, by tying together particles of soil with silk. If the soil is too hard, larvae may web together leaf debris and other material to form a cocoon on the soil surface. The pupa is reddish brown in color, and measures 14 to 18 mm in length and about 4.5 mm in width. Duration of the pupal stage is about eight to nine days during the summer.

Damage. This species seemingly displays a very wide host range, with over 80 plants recorded, but clearly prefers grasses. The most frequently consumed plants are field corn and sweet corn, sorghum, Bermudagrass, and grass weeds such as crabgrass. When the larvae are very numerous they defoliate the preferred plants, acquire an "armyworm" habit and disperse in large numbers, consuming nearly all vegetation in their path. Many host records reflect such periods of abundance, and are not truly indicative of oviposition and feeding behavior under normal conditions. Field crops are frequently injured, including alfalfa, barley, Bermuda grass, buckwheat, cotton, clover, corn, oat, millet, peanut, rice, ryegrass, sorghum, sugarbeet, sudangrass, soybean, sugarcane, timothy, tobacco, and wheat. Among vegetable crops, only sweet corn is regularly damaged, but others are attacked occasionally. Other crops sometimes injured are apple, grape, orange, papaya, peach, strawberry and a number of flowers. Weeds known to serve as hosts include bentgrass, crabgrass, Johnson grass, morning glory, nutsedge, pigweed and sandspur.

Larvae cause damage by consuming foliage. Young larvae initially consume leaf tissue from one side, leaving the opposite epidermal layer intact. By the second or third instar, larvae begin to make holes in leaves, and eat from the edge of the leaves inward. Feeding in the whorl of corn often produces a characteristic row of perforations in the leaves. Larval densities are usually reduced to one to two per plant when larvae feed in close proximity to one another, due to cannibalistic behavior. Older larvae cause extensive defoliation, often leaving only the ribs and stalks of corn plants, or a ragged, torn appearance. \

Larvae also will burrow into the growing point (bud, whorl, etc.), destroying the growth potential of plants, or clipping the leaves. In corn, they sometimes burrow into the ear, feeding on kernels in the same manner as corn earworm, Helicoverpa zea. Unlike corn earworm, which tends to feed down through the silk before attacking the kernels at the tip of the ear, fall armyworm will feed by burrowing through the husk on the side of the ear.

Control. Cool, wet springs followed by warm, humid weather in the overwintering areas favor survival and reproduction of fall armyworm, allowing it to escape suppression by natural enemies. Once dispersal northward begins, the natural enemies are left behind. Therefore, although fall armyworm has many natural enemies, few act effectively enough to prevent crop injury.

Numerous species of parasitoids affect fall armyworm. These include two species of Braconid wasps and a species of Tachinid fly. The predators of fall armyworm are general predators that attack many other caterpillars. Among the important predators are ground beetles, the striped earwig, the spined soldier bug, and the insidious flower bug. Vertebrates such as birds, skunks, and rodents also consume larvae and pupae readily. Predation may be quite important, \ depending on the area and season.

Numerous pathogens, including viruses, fungi, protozoa, nematodes, and a bacterium have been associated with fall armyworm (Gardner et al. 1984), but only a few cause epizootics. Among the most important are the S. frugiperda nuclear polyhedrosis virus (NPV), and the fungi Entomophaga aulicae, Nomuraea rileyi, and Erynia radicans. Despite causing high levels of mortality in some populations, disease typically appears too late to alleviate high levels of defoliation.

Insecticides are usually applied to sweet corn in the southeastern states to protect against damage by fall armyworm, sometimes as frequently as daily during the silking stage. It is often necessary to protect both the early vegetative stages and reproductive stage of corn. Because larvae feed deep in the whorl of young corn plants, a high volume of liquid insecticide may be required to obtain adequate penetration. Insecticides may be applied in the irrigation water if it is applied from overhead sprinklers. Granular insecticides are also applied over the young plants because the particles fall deep into the whorl.

The most important cultural practice, employed widely in warmer climates is early planting and/or early maturing varieties. Early harvest allows many corn ears to escape the higher armyworm densities that develop later in the season.

                                                                                   The Armyworm, Pseudaletia unipuncta

               The armyworm is sometimes called "true armyworm" to distinguish it from other species that include "armyworm" in the common name.

                                                                                                                 

                                                                     True Armyworm larvae.  Image courtesy of Frank Peairs, Colorado State University, United States, Bug

Description. The adults are light reddish brown moths with wing spans measuring about 4 cm. The forewing is fairly pointed, appearing more so because a transverse line of small black spots terminates in a black line at the anterior wing tip. The forewing is also marked with a diffuse dark area centrally containing one or two small white spots. The hind wings are grayish, and lighter basally. Larvae attain a body length 4, 6, 10, 15, 20, and 35 mm, respectively, during instars one through six. Except for the first instar, which is pale with a dark head, the larvae of the armyworm are marked with longitudinal stripes throughout their development. The head capsule is yellow or yellow-brown with dark net-like markings. The body color is normally grayish green, but a broad dark stripe occurs dorsally and along each side. A light subspiracular stripe often is found laterally beneath the dark stripe.

Life Cycle. Mating commences one to three days after moths emerge from the soil, and usually four to seven hours after sunset. Females produces an average of 5 egg masses (range: one to 16 eggs) with 500 to 1500 per female over a lifetime... Feeding is necessary for normal oviposition. The eggs are white or yellowish, but turn gray before immediately before hatching. Eggs are spherical, and measure about 0.54 mm (range 0.4 to 0.7 mm) in diameter. The egg surface appears to be shiny and smooth, but under high magnification fine ridges can be observed. The egg clutches are covered with an adhesive secretion that is opaque when wet but transparent when dry. As the adhesive material dries it tends to draw together the foliage, almost completely hiding the eggs.

Mean longevity at warm temperatures is about nine days in males and 10 days in females (range: three to three to 25 days) whereas at cool temperatures mean longevity of males is 19 days and females 17 days.

Larvae: Larvae normally display six instars, though up to nine instars have been observed. Mean head capsule widths (range) are 0.34 (0.30-0.37), 0.55 (0.49-0.63), 0.94 (0.83-1.12), 1.5 (1.29-1.70), 2.3 (2.08-2.56), and 3.3 (3.04-3.68) mm, respectively, for instars one through six. Head capsule widths increase slightly with increased temperature up to about 30°C. Larvae attain a body length 4, 6, 10, 15, 20, and 35 mm, respectively, during instars one through six. Except for the first instar, which is pale with a dark head, the larvae of the armyworm are marked with longitudinal stripes throughout their development. The head capsule is yellowish or yellow-brown with dark net-like markings. The body color is normally grayish green, but a broad dark stripe occurs dorsally and along each side. A light subspiracular stripe often is found laterally beneath the dark stripe.

Although not surviving year-round in cold winter areas, larvae apparently overwinter at intermediate levels, and in warm weather areas all stages may be found during the winter. The number of generations varies among locations, but in North America two generations occur annually in Ontario, Canada, whereas in the USA there are two to three generations in Minnesota and New York, four to five generations are reported in Tennessee, and five to six in southern states. A complete generation requires 30 to 50 days.

Pupae: Larvae pupate in the soil, often under debris, at depths of 2 to 5 cm. Pupation occurs in an oval cell that contains a thin silken case. The pupa is moderate in size and robust, measuring 13 to 17 mm long and 5 to 6 mm wide. The pupa is yellowish brown initially, but soon assumes a mahogany brown color. The tip of the abdomen bears a pair of hooks. Duration of the pupal stage is seven to 14 days during summer but longer early and late in the season, sometimes lasting 40 days.

Armyworm generally prefers to oviposit and feed upon plants in the family Gramineae, including weedy grasses. Thus, such grain and grass crops as barley, corn, millet, oats, rice, rye, sorghum, sugarcane, timothy, and wheat may be consumed, as well as wild or weed grasses. During periods of abundance larvae feed more generally, damaging such crops as alfalfa, artichoke, bean, cabbage, carrot, corn, celery, cucumber, lettuce, onion, parsley, parsnip, pea, pepper, radish, sugarbeets, sweet potato, watermelon, and others. Adults feed on nectar of various flowers and sometimes feed on other sweet foods such as ripe and decaying fruit.

Armyworm occurs in many areas of the world, including North, Central and South America, southern Europe, central Africa, and western Asia.  In North America, it is most abundant east of the Rocky Mountains where it is known principally as a grain pest. It does not overwinter in northern latitudes, but disperses northward each spring, and then southward during the autumn.

Larvae initially skeletonize foliage, but by the third instar they eat holes in leaves, and soon afterwards consume entire leaves. Larvae of armyworm are notorious for appearing out of nowhere to inflict a high level of defoliation. This occurs for several reasons:

·         a highly clumped distribution of young larvae, with most of the crop not infested until larvae are nearly mature and become highly mobile;

·         a tendency by larvae to feed on grass weeds preferentially, moving to crops only after the grass is exhausted;

·         occurrence of a preponderance of feeding, about 80%, in the last instar;

·         the nocturnal behavior of larvae, which makes them difficult to observe during the day;

·         and the gregarious and mobile behavior of mature larvae, which form large aggregations or bands (hence the common name ‘army' worm).

Natural Enemies

The importance of natural enemies, especially parasitoids, has been studied, though nearly all data are derived from periods of high armyworm density, which is not typical for this insect. Over 60 species of wasp and fly parasitoids are known, and vary considerably from time to time and place to place in importance. Examples are the wasp parasitoids Meteorus autographae, and Cotesia marginiventris.

Predators readily consume armyworm larvae. Ground beetles (Carabidae) are especially effective because larvae spend a great deal of time in association with soil, but various predatory bugs (Hemiptera: various families), ants (Hymenoptera: Formicidae), and spiders (Araneae: Lycosidae and Phalangiidae) also feed on armyworm.

Avian predators are often credited with destruction of armyworms. The bobolink, Dolichonyx oryzivorus (Linnaeus), prospers during outbreak years and has sometimes been called the ‘armyworm bird' in North America. Other birds of note include the crow, Corvus brachyrhynchos Brehm, and starling, Sturnus vulgaris Linnaeus.

Diseases commonly infect armyworms, especially during periods of high density. Bacteria and fungi, particularly the fungus Metarhizium anisopliae, are reported in the literature.

Nematodes are sometimes considered to be important mortality factors. However, undoubtedly the most important diseases are viruses; several granulosis, cytoplasmic polyhedrosis, and nuclear polyhedrosis viruses often kill virtually all armyworms during periods of outbreak, especially when larvae are also stressed by lack of food or inclement weather.

Armyworm attains high densities irregularly, often at 5 to 20 year intervals. The exact cause is unknown, but outbreaks often occur during unusually wet years and are preceded by unusually dry years. Armyworm is not well adapted for hot temperature; survival decreases markedly when temperatures exceed about 30°C. Consequently, at southern latitudes populations are higher early and late in the year, but at northern latitudes it is a mid-season pest.

Management. Adults can be captured with blacklight traps, and a sex pheromone has been identified and can be used for population monitoring. It is advisable to examine crop fields for larvae, especially if moths have been captured in light or pheromone traps. Fields should be examined at dawn or dusk, because larvae are active at this time. If it is necessary to check fields during the day, it is important to sift through the upper surface of the soil and under debris for resting larvae.

Cultural practices have limited effect on armyworm abundance due to their highly dispersive behavior. However, grass weeds are a focal point of infestation, and should be eliminated, if possible. Not surprisingly, no-till and minimum tillage fields experience greater problems with armyworm, relative to conventional tillage fields. Proximity to small grain crops is considered to be a hazard due to the preference of moths for such crops, and the suitability of grains for larval development. In Virginia, destruction of winter cover crops by herbicide application is more favorable to armyworm survival than is mowing of cover crops, apparently because predators are more disrupted by herbicide treatment. Prior to the availability of effective insecticides, deep furrows with steep sides were sometimes plowed around fields to prevent invasion by dispersing armyworm larvae. Although this approach remains somewhat useful, it is rarely practiced.

Larvae will consume wheat bran or apple pomace baits treated with insecticide, but foliar and soil-applied insecticides are also effective, and used frequently.

Cutworms. Granulate cutworm: Agrotis subterranean, Variegated cutworm: Peridroma saucia, Black cutworm, Agrotis ipsilon The larvae or caterpillars of some moths are called cutworms (Agrotis,  Amathes, Peridroma,  Prodenia spp.) because of the manner in which they cut down young plants as they feed.

There are a great many species of cutworms. They vary as to damage done and host plants preferred. Generally they destroy more of the plant than they eat. Their numbers vary greatly from year to year and when numerous may destroy as much as 75% of a crop. Cutworms injure plants in four major ways: solitary surface cutworms cut off young plants at or slightly above or below the soil line, sometimes dropping the severed plants into their burrows. Because most of the plant is not eaten, these cutworms do great damage, attacking and felling new plants nightly. The black, bronzed, clay-backed and dingy cutworms are in this group; climbing species such as  the variegated and spotted cutworms climb the stem of trees, shrubs, vines, and crops and eat the leaves, buds and fruit; subterranean species, particularly the pale western and glassy cutworms, remain in the soil and feed upon roots and underground parts; and army cutworms occur in great numbers and consume the tops of plants and then "marching" on to other fields.

The many species of cutworms can be quite distinct. Many are stout, smooth, soft-bodied, plump caterpillars. These vary from brown or tan to pink, green or gray and black. Some are all one color, others spotted or striped. Some larvae are dull, others appear glassy. The adults are generally very robust brown or black moths showing various splotches, blotches or stripes in shades of gray, brown, black or white.

                                                                                            

                                                                                         One of many species of cutworm.  Image courtesy Neil Phillips.

Most cutworms pass the winter as partially grown larvae. Thus they are already large, voracious feeders when transplants and seedlings are set out in the fields. A few species pass the winter as pupae or hibernating moths. Overwintering cutworms may live under trash or bark, in clumps of grass or in earthen cells in the soil. These cutworms become active and begin feeding as the weather warms in spring, remaining hidden under debris or in the soil and feeding at night. Many species continue to feed well through June, then pupate in the soil to emerge later as moths. Normally there is only one generation per year. The moths crawl from their brown pupal cases in the soil and climb up through the soil, following the tunnel made by the burrowing larva. If this tunnel is blocked, the fragile moth cannot escape the soil. Cutworm abundance and development is greatly affected by weather, especially rainfall. The moths mate and lay eggs in late summer, beginning the next generation. The moths often seek out grassy or weedy areas to lay their eggs, which are usually deposited on plant stems or in the soil. One female may lay hundreds of eggs. The hatching larvae feed until cold weather and then hide for the winter in a sheltered, dry place.

Several cultural practices may offer some degree of control-these include: plow and fallow fields in mid- to late summer to prevent the laying of eggs; plow in the fall to expose the larvae or deeply bury the pupae; cultivate fields in the spring after vegetation has appeared and grown a few inches, then delay seeding to starve the cutworms; plan rotations to avoid row or hill crops following a grassy sod. Plow sod fields in late summer or early fall the year before planting; cultivate frequently to injure and expose hiding cutworms to predators; the construction of ditches and dusty furrows may interrupt armyworms; place foil or paper wraps or cardboard collars around transplants; extend a few inches into the soil and several inches up the stem; dig in the soil around damaged or adjacent plants in the row; find and destroy the cutworm; plant a thick "trap crop" of sunflower, a favored host, around the perimeter of the garden; find and destroy attacking cutworms daily; establish a tanglefoot band on trees being attacked by climbing cutworms.

Chemical treatments are available as either homemade or commercial poison baits or as insecticide treatments directed to the soil surface or on and around the plants. Granular insecticide treatments, applied to protect the seed and developing seedlings from soil insects, are of little, if any, value in controlling cutworms.

Corn Earworm, Tomato Fruitworm, Cotton Bollworm- Heliocoverpa zea.  The larva of the moth Helicoverpa zea (formerly in the genus Heliothis) is a major agricultural pest throughout the United States. It is quite omnivorous feeding on may differ species of plants. Accordingly, the species has been given many different common names. When the larva consumes cotton, it is known as the cotton bollworm. When it feed on corn, it is known as the corn earworm. And when it consumes tomatoes, it is known as the tomato fruit worm. It has also been known to consume many other crops. As a result the impact of this pest has been and continues to be significant

Helicoverpa zea larvae are quite variable in color ranging from green, brown, or pinkish with darker longitudinal stripes; they grow to about 3.7 cm (1.5 inches) in length. Adults are most active during the evening and at night with a body length of approximately 1.9 cm (0.75 inches) and a wingspan of 1 to 1.5 inches. Its body is yellowish tan with distinctive double lines that are reddish brown, olive green or grey. The forewing has several dark marking and a central brown dot. The hindwings are pale in color and surrounded by a dark brown border. It has a tan colored head with bright green eyes.

                                                                                            

                                                                               Corn earworm feeding on silk and kernels.  Image courtesy of Cyanocorx 

The corn earworm is considered to be a major agricultural pest, with a large host range encompassing not only corn, but also numerous other crop plants. Pesticides are one method by which corn earworm populations are controlled; however, since they have been widely used, the insects are resistant to many pesticides. The use of biological controls such as the bacterium Bacillus thuringiensis and various forms of nematodes is also common, although not without its own problems. Corn earworms are only variably vulnerable to the bacterium, and nematodes are only effective once the larvae have pupated and dropped to the ground.

The corn earworm is found in temperate and tropical regions of the world.  It is mainly found in North America, but is not found in northern Canada and Alaska, as it cannot overwinter in these areas. Corn earworm regularly migrates into northern regions from southern regions depending on winter conditions.

Eggs are individually deposited on leaf hairs and corn silks and hatch in about 3 to 4 days. Following hatching, larvae normally feed on the reproductive structures of the plant and usually develop through four to six instars. Older larvae become aggressive and cannibalistic, resulting in one or two larvae per ear.  Mature larvae migrate to the soil, where they pupate for 12 to 16 days. Adult moths collect nectar or other plant exudates from a large number of plants, and live for 12 to 16 days. Females lay up to 2500 eggs in their lifetimes.

Damage-Control.  Corn-The corn earworm feeds not only on the whorl, tassel, and silks, but on the kernels of the ear itself. Severe feeding on the leaves gives the plant a ragged appearance. Feeding on kernels at the tip of the ear creates an avenue of entry for diseases, especially molds in seed corn. Similar damage in sweet corn results in an un-salable product, especially for the fresh market. Home gardeners and even some sweet corn processors often accept some damage by corn earworm because feeding is commonly limited to ear tips, which can be cut off before processing or home use. Unfortunately, the presence of damage and a live earworm beneath the husk is usually not acceptable in the fresh produce market. In seed corn production, damaged kernels represent yield loss. Just as importantly, removing damaged kernels from seed lots results in additional losses because substantial amounts of undamaged seed corn are also discarded during the mechanical sorting process.

Management of this pest in corn often lies with planting resistant hybrids and altering planting dates to avoid high densities of corn earworms. Resistant hybrids limit the amount of injury to both the leaf and the ear. A combination of silks that are antibiotic to larvae and husks that are tight around the ear to alter larval behavior offer the most effective type of resistance. Because of the tightness of the husk around the ear, feeding is limited to the ear tip, resulting in small larvae or larvae that leave the ear before completing development. Some birds suppress corn earworm populations and reduce the amount of injury to the ear. Neither crop rotation nor tillage significantly influences corn earworm survival. However, early-planted crops are most likely to escape peak populations of egg laying moths. In addition, because egg-laying moths prefer corn to beans, tomatoes, and other crops, borders or strips of corn planted as a trap crop around or within fields of other vegetables may reduce earworm densities on these less preferred crops. This approach is likely to provide some benefit only if the corn is silking at the same time as the beans, tomatoes, or other crops are setting pods or fruit.

Chemical control of the corn earworm can be expensive; most spraying occurs in sweet corn fields where a majority of the market value is in the quality of the ears. Since larvae move down the silk channels as soon as they hatch, the timing of insecticide applications is very important. As the larvae move down the silks and under the husk of the ear, insecticide sprays become ineffective. For insecticides to work effectively, spray residues need to be present on the silks where the eggs hatch. There will be no insecticide residue on new silk growth. 

Damage-Control-Tomatoes. When there is fruit present, the tomato fruitworm will complete its larval development inside fruit. Early stage larvae enter fruit at the stem end when it is between 0.75 to 2 inches in diameter. During development, caterpillars may emerge from one fruit and enter another. Their feeding results in a messy, watery, internal cavity filled with cast skins and feces. Damaged fruit will ripen prematurely. Late in the season, small larvae will also enter ripe fruit. Small larvae are difficult to detect and, thus, may be a problem in processing tomatoes for the canner. Tomato fruitworm is less of a problem for fresh market tomatoes because damaged fruit are easily culled at harvest.

                                                                                                      

                                                                                       Larvae feeding on tomato fruit.  Image courtesy of Flex

Management of tomato fruitworm requires careful monitoring for eggs and small larvae. When control is needed, it is essential to treat before large numbers of larvae enter fruit, where they are protected from sprays. Trichogramma parasites and other natural enemies often destroy significant numbers of eggs, so it is important to check for parasites before making treatment decisions. Except in the desert valleys, early-season processing tomatoes rarely need treatment. Late-season fields may be more seriously affected.
Naturally occurring beneficial insects are very important in the biological control of tomato fruitworm, especially in the Delta area and the Sacramento Valley. These include Trichogramma spp. egg parasites, the larval parasite Hyposoter exiguae, and predators such as bigeyed bug and minute pirate bug. Conserve these parasites whenever possible and monitor their presence.

A tomato fruitworm egg parasite, Trichogramma pretiosum, is available from many commercial insectaries. Inundative releases of 100,000 parasites/acre during the period of fruitworm oviposition and when fruit are susceptible to fruitworm feeding can reduce damage to acceptable levels. Monitor releases using the egg sampling technique to determine the success of the release (indicated by black, parasitized eggs) and use the table below to determine if pesticide treatments are needed. Be sure to monitor the releases to make certain that parasitism is occurring.

Damage-Control-Cotton. Cotton bollworm larvae damage bolls and squares. Larvae chew holes into the base of bolls and may hollow out locks. Moist frass usually accumulates around the base of the boll. Larvae may also chew shallow gouges in the boll surface, which can become infected with rot organisms. Squares injured by cotton bollworm usually have a round hole near the base. Fifth-instar larvae are the most destructive; they not only damage more fruit than do earlier instars, but they damage larger fruit that are harder for the plant to replace.

                                                                                                   

                                                                                         Late insar larva leaving cotton boll.  Image courtesy USDA.

The impact of a bollworm infestation depends on the number of larvae present, the age of the larvae, and the timing of damage relative to the crop's fruiting cycle. Although large larvae do most of the damage, it is not possible to kill a significant proportion of them once they are older than the third instar. Monitoring and control must therefore be aimed at the eggs and small larvae.

Natural enemies are very important in managing populations of bollworms, especially in the San Joaquin Valley. Damaging populations usually do not appear until late in the season, after treatments for other pests have disrupted natural enemies. Insecticides are needed only if the population exceeds the treatment threshold while the crop has a significant number of squares or green bolls that will have time to develop into mature bolls by season's end. There is no need to treat once bolls begin cracking, because most bolls are too mature by that time to be susceptible and squares still present will not have time to mature. The same principle applies to long-season desert valley crops, except that there are two periods when injury can occur – one in each fruiting cycle.

Many predators and parasites combine to substantially maintain cotton bollworm populations at low levels. Insecticide sprays for other pests will disrupt this natural control and may result in severe outbreaks of this pest.

Cultural Control. A recently developed transgenic cotton, Bollguard II, offers suppression of cotton bollworm, along with beet armyworms, pink bollworm, and tobacco budworms.

Cotton bollworms are attracted to succulent, rank-growing cotton plants; keep water, fertilizer, and plant density at recommended levels to avoid rank growth. Because populations seldom reach damaging levels before late summer, manage the crop for early maturing and plan to defoliate by late September.

 

                                                                          Pyralidae-Snout Moths

The European Corn Borer-Ostrinia nubilalis.  This is a pest of grain, particularly corn as its name implies. The insect is native to Europe originally infesting varieties of millet including broom corn. The European corn borer was first reported in North America in 1917 in Massachusetts, but was probably introduced from Europe several years earlier. Since its initial discovery in the Americas, the insect has spread into Canada and westward across the United States to the Rocky Mountains.

The corn borer moth is about one inch long with a one inch wingspan. The female moth is light yellowish-brown with dark irregular, wavy bands across the wings. The male is slightly smaller and darker in coloration. The tip of its abdomen protrudes beyond its closed wings. The fully-grown larva is three-quarters to one inch in length. This borer is usually flesh-colored, but may range from light gray to faint pink, with conspicuous small, round brown spots on each segment.

                                                                                        .

                                                                                             

                                                 European Corn Borer.  Left. Image courtesy USDA,ARS Right. Image courtesy http://www.entomart.be/

European corn borer caterpillars damage the ears of corn, as well as the stalks, chewing tunnels which cause the plants to fall over. Biological control agents of corn borers include the parasitoid Trichogramma. Bt corn, a variety of transgenic maize, has had its genome modified to include a gene from the Bacillus thuringiensis, ssp. kurstaki. As a result the corn variety produces a toxin which affects the corn borer, and as critics have pointed out, beneficial predatory insects as well.

Female corn borer moths lay clusters of eggs on corn leaves, usually on the underside of the leaf. The egg masses, or clusters, are laid in an overlapping configuration and are whitish-yellow in color. As the larvae develop inside their eggs, the eggs become more and more.

 

 

 Greater Wax Moth, Galleria mellonella, Lesser Wax Moth, Achroia grissella.  As indicated there are two species of wax moths. Both species typically resides in milder climates and can be prevalent year-around in areas such as Southern California because of the warm climate.  As their names implies wax moths do not attack any stages of the bees but are a persistent pest of unattended honeycomb.  Honeycomb that is present in an active area of the hive or full of honey is rarely attacked but empty comb that is stored or to a lesser extent in an area of a hive that is not occupied by adult bees can be destroyed in a fairly short time. The adults of these moths are almost always present in areas where beekeeping is practiced.

 It has been estimated that annually, beekeepers lose nearly 5 million dollars in damages due to these pests. There are many methods of control that beekeepers have adopted to ensure that these moths do not ruin the combs.

During its life a female wax moth lays 300 to 600 eggs with some laying up to 1,000. The eggs are laid on combs or in cracks and crevices on the wooden parts of hives. The eggs of both moth species are small (about 0.5 mm long). In warm conditions they hatch in about five days, but in cool conditions hatching may take 30 days. The duration of the larval stage depends on temperature and the food supply. It may be six months if the weather is cold and there is a shortage of food. With warm conditions and abundant food, larvae can be fully grown in one month. This is when comb damage is greatest. When fully grown, the larvae move to a wooden part of the hive to pupate in silken cocoons.  With the greater wax moth many cocoons may be clustered together. The pupal stage lasts about 10 days in warm conditions. The cocoons of the lesser wax moth occur singly rather than in clusters and lasts about 16 days during warm conditions

The bees themselves are the best form of control for these moths. They keep the populations at very low numbers and it is only when they are not strong enough that the moth populations will drastically increase. Beekeepers must make sure that the hives have active, populated colonies that are clean and free of debris. This will help to ensure the survival and strength of the bees that can then control the populations of the moths.  Sign of an infestation are the wax moth larvae, their silken tunnels intertwining in the comb, their fecal pellet and the silken cocoons.  The wooden parts of the hive (e.g. frames and hive bodies) typically have small concave indentations where the larvae have eaten out an area for pupation. Wax moth infestations can reduce combs to a mass of debris littered with silk tunnels (Figure 34)

In the colder climates, storing the beeswax combs in freezing winter temperatures will stop there from being any chance of a moth infestation. Lesser wax moths need warm climates to thrive. There is also a fumigant known as paradichlorobenzene (PDB) that is used to destroy these moths. This can only be used on combs that are in storage.  Carbon dioxide can be used to fumigate combs that are filled with honey. Heating or freezing combs filled with honey also allow the honey to still be sold. The hotter or colder the temperature is, the less time that is required to make sure that the comb has been protected. So far no traps have been found that completely protect honeycombs from the invasion of lesser wax moth larva.

Figure 33.  A mature wax moth larvae.

Indian Meal Moth. This species is one of many that attack primarily stored products. It prefers coarser grades of flour, and is therefore the most common pest in whole-wheat or graham flour and cornmeal but will attach a wide variety of other stored products.  Heavy webbing produced by the larvae typically extends throughout the infestation.  If present the adult moth can be found flying around the structure.  Their coloration is quite diagnostic of the species.

                                                                   

                                                  Heavy Infestation Indian Meal Moth. Image courtesy of http://bugguide.net/user/view/4

The Indian meal moth is a handsome moth with a wing expanse of nearly three-quarters of an inch. It is easy to distinguish from other grain pests by the peculiar markings of the forewings; they are reddish brown with a copper luster on the outer two-thirds, but whitish gray on the inner or body ends. The hind wings lack distinctive markings and are more or less uniformly gray. Adults can be seen resting on the product or walls of the storage area. The adults fly at night and are attracted to lights.

The eggs of the Indian meal moth are whitish, ovate and very small. Because of their small size, they are difficult to see without the aid of a microscope. Eggs are deposited on the grain surface singularly or in groups of twelve to thirty.

Newly hatched larvae are very small and difficult to see. Larger larvae are usually yellowish, greenish, or pinkish. Fully grown larvae are one-half to five-eights of an inch in length with a brownish head capsule. Larvae have three sets of legs near the head (thoracic legs) and five sets of prolegs on the abdomen. Larvae of the meal moth spin a web as they become fully grown and leave behind silken threads wherever they crawl. The webbing is often sufficiently abundant to attract attention. Loosely clinging webbing on the grain is characteristic of this pest.

                                                                                                                                 

                                                    Indain Meal Moth Adult.  Image courtesy Kaldari. Indian Meal Moth Larva. Image courtesy of Pudding4brains

As long as the temperature within a storage area remains above 50° F, the Indian meal moth can survive and reproduce. A typical life cycle (egg to adult) is completed in forth to fifty-five days. A potential for seven to nine generations per year exists; however, because of cool temperatures during the winter months fewer generations are usually completed. Under optimal conditions, the entire life cycle can be completed in approximately twenty-eight days.

A mature female lays 100 to 300 eggs on food material, either singularly or in groups of twelve to thirty. Larvae begin to hatch in two to fourteen days, depending on environmental conditions. Newly hatched larvae feed on fine materials within the grain and are small enough to pass through a sixty mesh screen. For this reason, it is difficult to exclude larvae from most packaged foods and grain.

These insects are always present in the environment and will attack any of these products if given time.  The important point here is that if any of these products remain unprotected on the shelf, in a super market, home, warehouse or any other situation for that matter for an extended period of time they will become infested with one or more of these insects.  The length of time before an infestation occurs will vary depending on the situation but a year or more is way more than a product should remain unprotected, sold, consumed or discarded.

As to the where the source of the infestation initiates there are many possibilities.  Take for example a hypothetical package of infested noodles that is stored in a kitchen cabinet.  If they have been in the cabinet for a long period of time (years) there is a pretty good chance that the infestation initiated in the cabinet.  But those noodles have probably had quite a route prior to reaching the homeowner and anywhere along where they could have been infested.  They could have been infested at the manufacturing plant or in trucks or ships while they were transported to a warehouse or even at the grocery story prior to purchase.

As far as protecting these products from infestation this is a difficult matter.  The larval and/or adult forms of these pests are capable of penetrating most types of packaging including cardboard, tinfoil and soft plastics.  They cannot eat their way through glass, canned goods or harder plastics.

Generally speaking most of these pests have a few characteristics in common.  Namely most are small averaging 1/8^th to 1/4^th inch or smaller (mites) in length in the adult stage.  More importantly the early immature stages (eggs and early instar larvae) are nearly microscopic in size.  Of course this makes early detection of an infestation difficult.  In addition most of these insects lay a large number of eggs (several hundred per female) and have a relatively short life cycle (several weeks from egg to adult).  As a result a rather large infestation can develop quite quickly.

Successful control starts with identification of the pest and determining the extent of the infestation.  Any small moths or beetles found in the vicinity of stored products are a pretty good indication that an infestation does exist.  At that point an inspection of the products is necessary.  Most of these pests leave the host when approaching the pupal stage and frequently eat their way out of the packaging.  As a result small emergence holes (typically about the diameter of pencil lead) will appear on the outside of the packaging.  An inspection of the suspect product may reveal webbing (produced by some of the moth larvae), the feeding larval stages, larval feces or damaged product.

If the infestation occurs in a kitchen cabinet or any other area where multiple products occur everything must be inspected except those products that are packaged with those types of materials that cannot be penetrated by the pests.  Keep in mind that since many of the stages of these small insects cannot be readily detected a product that appears to be pest free may be infested.

Any products that are obviously infested should be discarded or destroyed.  The question then remains as to what should be done with those that may or may not be infested keeping in mind that the eggs and early instars of these pests are almost impossible to see with the unaided eye.  Discarding these may not be an option depending on their value.  If this is the case there are really only two options to kill the existing pests without contaminating or harming the products.  Fumigation is a possibility but is generally limited to large scale operations or very valuable products.  On a small scale heat is viable option.  As with all insects stored product pests cannot survive when held at temperatures much above 100 F for any extended period of time.  A few minutes in a microwave are also very effective.  Insects are much more tolerant of very low temperatures than high temperatures.  As a consequence freezing or refrigeration may not be an effective means of treatment.

The Pink Bollworm life cycle includes four stages. These are the egg, larva, pupa, and adult. The time required from egg to egg varies because of temperature and other conditions but generally is about one month during the summer months.

 

Female pink bollworm moths lay eggs singly or, more commonly, in small groups. Eggs are white when first laid but then turn orange, and later the larval head capsule is visible prior to hatching. The eggs are small and difficult to see without some magnification. Eggs hatch in about three to four days after they are laid. Eggs of the first field generation in the spring are often laid on vegetative cotton plants near cotton squares and sometimes on squares. Second and subsequent generation eggs are usually laid under the calyx of bolls.

 

Larvae immediately begin to bore into squares or bolls after hatching. In squares, larvae complete most of their development before blossoming occurs and often cause rosetted blooms. Final development is completed in the blossom. In bolls, larvae feed within one to five seeds to complete development before exiting and dropping to the soil for pupation. While moving from seed to seed, the larva causes damage by cutting through the lint with its mouthparts. Lint is also damaged as the larva tunnels out of the boll. Larvae are white with a brown head when they hatch. They have four stages of growth (instars) and begin to turn pink in the fourth instar. They generally require 12–15 days to complete development after which they go into pupation.

 

Most pupation occurs in the top layer of soil beneath cotton plants. The pupa is brown and approximately one-half inch long. It does not feed or move about during the pupal period of seven to eight days.

 

Adult pink bollworms are mottled brown to gray moths and are about one half inch long. They emerge from pupae in an approximately 1:1 male to female ratio. There is a time period of two to three days after emergence during which the female mates and prepares to lay eggs. After this preoviposition period the female lays most of her eggs in about ten days. Both male and female adults feed primarily on nectaries located on the bottom of cotton leaves and may live for one to two months. The female produces a sex pheromone that aids the male in locating her for mating purposes.

 

Understanding the seasonal cycle of this pest species is key to exploiting cultural control techniques which can be responsible for season long control of the pink bollworm.

The seasonal cycle is intimately tied to the cultivation of our cotton crop, because domestic cotton is the only host through most of the pink bollworm’s

range.

 

Winter. The pink bollworm overwinters as a fully developed larva (fourth instar). During this period the pink bollworm is in a state of arrested development called

diapause. The larva often spins a loose, silken web or cocoon in which it remains until the late winter and spring. Overwintering larvae may be found in bolls in the

soil or on plants which remain unplowed through the winter. Often times the larvae may be found within the hollowed out seeds of undestroyed bolls. The larvae may also be found directly in the soil outside of seeds or bolls. In Arizona and southern California, about 50% of diapausing larvae live through the winter in the silken cocoons in the top two to three inches of soil while the other 50% remain in whole or fragmented bolls and squares.  Most overwintering occurs in the cotton field, although some may occur wherever cotton debris is deposited.

 

Spring. Once diapause is completed, the larva begins to respond to temperature and moisture conditions and ultimately pupates in the spring. Though moths may be captured virtually any month of the year, most adults will emerge from pupae within the soil in the spring. Adults must navigate through the cracking soil in order to

emerge, dry their wings, and start the first field generation.

 

Adults move about searching for cotton and are capable of travelling long distances in order to reach susceptible cotton. Most flight occurs at night (especially midnight to 3 a.m.) when temperatures and wind conditions are moderate (i.e., > 50°F and < 10 mph). Mating occurs, and a gravid female must lay most of her eggs in about 10 days after emerging. Squares which are capable of supporting pink bollworm larvae are deemed susceptible. This condition occurs when the sepals first part and the white petals

become visible. Usually this corresponds to a 10-day old square. Up to this point of cotton development, pink bollworms cannot successfully colonize cotton and willperish. This is termed “suicidal emergence.” Thus, adult moths that emerge about ten days or more prior to susceptible square die without contributing to the first field generation.

Larvae from eggs laid on susceptible squares feed inside the squares and often cause rosetted blooms. Rosetted blooms are flowers which have had their petals tied together with silk by the developing larva. Most of the feeding at this stage is concentrated on the developing pollen grains and other floral parts. This can interfere with the proper development of the new boll. Occasionally, the larva can travel to the bottom of the flower and begin feeding at the tip of the newly developing boll.

Summer

Fully developed larvae drop to the soil and pupate for seven to eight days before emerging as second generation moths. Each generation during the summer takes about 750 heat units (base 55°/86°F). This period is roughly equivalent to about one month in the low deserts. Depending on local conditions, pink bollworms are capable of passing through from one to four summer generations. The greater the number of generations that are possible for an area or allowed for by production decisions, the greater the chance is that damaging numbers will build-up. Once present on the plant, bolls become the preferred egg-laying site and feeding medium for the larvae.

 

Fall

Some larvae begin to prepare for winter diapause in late August, and this diapause accelerates rapidly after mid-September as day lengths begin to shorten. Diapause is caused primarily by shorter days (reduced photoperiod) and lower temperatures (£70°F), and therefore it predictably occurs at about the same time each year. A reducing percentage of pink bollworms continue to re-cycle throughout the fall months, and they can cause late season infestations. Limiting the number of small green bolls present after mid-September can drastically reduce the number of sites for pink bollworm re-cycling and overwintering. By late fall, if bolls are present, it is not unusual to have

multiple larvae per boll present. These latest bolls on the top of the plant are generally immature, have poor lint characteristics, and contribute little or nothing to yield

 

                                                                                                                                             

                                                                                                                    Pink bollworm larvae and adult.. Image courtesy of USDA-ARS.

 

                                                                                             Potato Tuberworm-Phthorimaea operculella

Potato tuber moth (Phthorimaea operculella), also known as the tobacco splitworm has a world-wide distribution. The body length is about 10mm and the wingspan is about 12mm. The larva is called potato tuberworm. The most economically important damage occurs predominantly through the larvae’s feeding on the tuber. In the field and in storage facilities, the larvae excavate tunnels throughout the potato tuber, often leaving mounds of frass near the tunnel entrances. This damage makes fresh potatoes unmarketable. In addition to their physical damage to the tubers, the tunnels allow the introduction of bacteria and fungi into the tuber. Larvae of P. operculella also damage the foliage by burrowing through the leaf petioles and creating transparent leaf blisters (figure 2). Infested plants can be recognized by the mines the larvae make in the leaves and stems and by the webbing together of adjacent leaves. Although potato tuberworms are primarily associated with potatoes, they have been observed feeding on other plants. Domesticated plants such as tomatoes, eggplants, peppers, and tobacco and wild solanaceous plants have served as host. The potato tuberworm is becoming a pest in North Carolina. In tobacco, the larvae are leaf miners and can cause severe damage to leaves, making them weigh less.

Moth activity correlates with temperature. In the Northern Hemisphere, peak populations of adult P. operculella have occurred from May through June in Israel, from June through August in Yemen, and in late summer in the United States.  Tuber moths move between crops and forage up to 0.15 mile to infest tubers or plants. Long distance movement of potato tuberworms is probably due to movement of infested tubers. The adult female moth lays between 150 and 200 eggs individually on the underside of potato leaves and stems or in the eyes of exposed tubers in the field or in storage. The recently laid eggs are pearly white ovals that become darker as they mature.

Larvae can be found either on the foliage or in the potato tuber. It is necessary to cut suspicious tubers to carefully check for signs of tuberworm damage and the presence of larvae or pupae. Larvae pupate in dead potato leaves, in soil, in cull piles, or on stored potato tubers. If these habitats are not available, larvae will seek other protected places for pupation, such as crevices in walls, floors, and crates, or other locations where the temperature is above freezing. Pupae form a silk cocoon overlaid with soil and debris available nearby. The number of generations each year and the length of the life cycle are influenced by temperature. The life cycle can be as short as 2 weeks insummer or as long as 7 months in winter.

Many cultural practices capable of reducing potato tuberworm populations in the field have are recommended.  These include: when possible avoid planting infested seed; tubers; when planning crop rotations, choose potato fields as distant from previous potato plantings as possible; destroy volunteer potato plants in uncultivated lands or other crop fields;  any effort to reduce the exposure of tubers to egg laying females or to larvae will reduce crop damage. These insects will not burrow through more than 2 inches of soil to reach the tuber. Therefore, extra hilling to increase soil coverage is encouraged. Furthermore, regular irrigation will reduce the number of soil cracks available for potato tuberworm entrance; sprinkler irrigation seals the soil and reduces soil cracking better than furrow irrigation; and to reduce exposure time, harvest mature tubers as soon as possible.

Since this pest can be an additional problem in storage the follow can be used. Advice for preventing infestations in storage includes detecting the first invading insects. Adult moths could probably be detected early with pheromone traps. Visual spotting of potatoes infested with larvae is more difficult because the insect’s tunnels at early stages of infestation are very small and very difficult to see. It is necessary to cut suspicious tubers to carefully check for larvae, pupae, and signs of tuberworm damage. Eliminating damaged tubers and treating the remainder with insecticide is critical. Only pesticides that are registered for use in storage facilities for the control of this insect pest can be used. Pyrethroids are effective on potatoes to be used for seed, while biological products such as Bacillus thuringiensis and baculovirus are safe on potatoes destined for consumption.

Potato tuberworm on tobacco leaf.  Image courtesy of David Jones, University of Georgia, Bugwood.org.  Damaged Potato.

 

                                                                               Tineidae-Fungus Moths. Moths.

Tineola bisselliella, known as the Common Clothes Moth, Webbing Clothes Moth, or simply Clothing Moth.  The caterpillars of this moth are considered a serious pest, as they can derive nourishment from clothing – in particular wool, but many other natural fibers – and also, like most moth of its relatives, from stored produce.

Its natural range is western Eurasia, but has been transported by human travelers to other localities. For example, it is nowadays found in Australia and North America. This moth prefers moist conditions, although low humidity will merely slow development. Webbing clothes moths are small moths whose adults grow to between 1 and 2 cm in length. Their eggs are tiny, most being under 1 mm long and barely visible. A female will lay several hundred during her lifetime; egg placement is carefully chosen in locations where they will have the best chance for survival.

                                                                                          

                                                                                               

                                                        Adult and larva of webbing clothes moth,  Images courtesy of (right) Olaf Leillinger and (left) Guido Gerding

The eggs are attached with a glue-like substance and can be quite difficult to remove. After the egg hatches, the larva will immediately look for food. Larvae can obtain their required food in less than two months, but if conditions are not favorable they will feed on and off for a long time. Whether it takes two months or two years, each larva will eventually spin a cocoon in which it will pupate and change into an adult. Larvae stay in these cocoons for between one and two months and then emerge as adults ready to mate and to lay eggs.

This species is notorious for feeding on clothing and natural fibers; they have the ability to turn keratin (protein of which hair and wool mainly consist) into food. The moths prefer dirty fabric for oviposition and are particularly attracted to carpeting and clothing that contains human sweat or other liquids which have been spilled onto them. They are attracted to these areas not for the food but for the moisture: the caterpillars do not drink water; consequently their food must contain moisture.

The range of recorded foodstuffs includes cotton, linen, silk and wool fabrics as well as furs; furthermore they have been found on shed feathers and hair, bran, semolina and flour (possibly preferring wheat flour), biscuits, casein, and insect specimens in museums. In one case, living T. bisselliella caterpillars were found in salt. They had probably just accidentally wandered there – as even to such a polyphagous species pure sodium chloride has no nutritional value – but still it attests to their robustness.

Both adults and larvae prefer low light conditions. Whereas many other Tineidae are drawn to light, Common Clothes Moths seem to prefer dim or dark areas. If larvae find themselves in a well-lit room, they will try to relocate under furniture or carpet edges. Handmade rugs are a favorite, because it is easy for the larvae to crawl underneath and do their damage from below. They will also crawl under moldings at the edges of rooms in search of darkened areas where debris has gathered and which consequently hold good food.

The eggs hatch into larvae, which then begin to feed. Once they have finished larval development, they pupate and undergo metamorphosis to emerge asimagines (adult moths). Adults do not eat; males look for females and females look for places to lay eggs. Once their job is done, they die. Contrary to what most people believe, adult T. bisselliella do not eat or cause any damage to clothing or fabric. It is the larvae which are solely responsible for this, and which spend their entire time eating and foraging for food.

                                                                                                   Moth Larvae with Urticating Hairs.

 

There are a number of moth caterpillars that possess urticating or stinging hairs.  These larvae are typically brightly marked.  Of course presence of these are considered a form of “warning” to advertized the fact to other animals that they pack a powerful punch.

Saddleback Caterpillar.  The saddleback caterpillar, Sibine stimulea, is the larva of a species of moth native to eastern North America. The species belongs to the family of slug caterpillars, Limacodidae. It is also known as the "packsaddle".

The caterpillars are primarily green with brown at either end, and a prominent, white-ringed brown dot in the center which resembles a saddle, hence the name. They feed on a large variety of plants, and the adults are dark brown, stout-bodied moths. In Florida, they are known to feed on ornamental palms such as the Adonidia merrilli (Christmas palm).

.Stings can be very painful. They can cause swelling, nausea, and leave a rash that can last for days. Individuals with sensitive skin are cautioned against coming into contact with them as the reaction can be more severe than the typical reaction. The primary nettling hairs are borne on the back of paired fleshy protuberances toward the front and hind ends of the body. There is also a row of smaller stinging organs on each side. This caterpillar feeds on many plants, including hibiscus and palms, but appears to show little host preference.

 

                                                                                                                      

 

Hag Moth.  The larva is distinctive, with no close analogues although it may be mistaken for the shed skin of a hairy spider or leaf debris. It has six pairs of curly projections, three long and three short from the flattened body, each densely covered in hairs. According to David L. Wagner, who experimented on himself, the hairs do not sting, contrary to popular belief. However, susceptibility can vary among humans and it may produce a reaction in some people. Some members of the family Limacodidae do sting. Like all Limacodids, the legs are shortened and the prolegs are reduced to suction cups. The 'arms' can fall off without harming the caterpillar.   The maximum length of larva is about 1 inch.  It is solitary and is not a very significant agricultural threat, but it is a common sight in orchards.

   The adult moth has a wingspan of up to 3 cm. The male has translucent wings, and the female is drab brown and gray, with yellow puffs on her legs. The day-flying female is said to mimic a bee, complete with pollen sacs, and the male mimics a wasp. They feed on a variety of deciduous trees and shrubs, not limited to: apple, ash, birch, cherry, chestnut, dogwood, hickory, oak, persimmon, walnut, willow.

 

                                                                                                                       

 

Puss Caterpillar. It is a convex, stout-bodied larva, almost 1" long when mature, and completely covered with gray to brown hairs. Under the soft hairs are stiff spines that are attached to poison glands. When touched, these poisonous spines break off in the skin and cause severe pain. Puss caterpillars feed on a variety of broadleaf trees and shrubs, and are most often found on oaks and citrus. In Florida there are two generations a year, one in spring and the other in fall. Natural enemies keep these caterpillars at low numbers during most years, but they periodically become numerous.

 

                                                                                                  

 

Io Moth.  Larvae are about 2 to 2-1/2 inches long full-grown, pale-green with a narrow, reddish stripe edged underneath with white that extends lengthwise along each side of the body. It appears spiny (numerous clusters of urticating hairs). Each body segment is equipped with several fleshy tubercles armed with numerous long, greenish venomous spines tipped with black. Pain is less severe than the puss caterpillar.

 

                                                                                                         

                                                                                                       Image Courtesy Michael Holryod

87. Fiery lawn skipper damage can be reduced by limiting thatch and overseeding with varieties of nonpreferrd grass species.

88. The corn earworm, tomato fruitworm and cotton bollworm all belong to the same species, namely Heloithis zea.

89. With the salt marsh caterpillar young larvae feed gregariously and skeletonize foliage.

90. With the corn earworm rarely are more than 1 or 2 later instar larvae found in an ear of corn due to the fact that older larvae become aggressive and cannibalistic. A synthetic version of its sex pheromone (codlemone) is now commercially available for the cabbage looper.  Pheromone traps are used to monitor field populations of this pest.

92. Wax moths rarely attack honeycomb that is present in an active area of the hive or full of honey but empty comb that is stored or to a lesser extent in an area of a hive that is not occupied by adult bees can be destroyed in a fairly short time.

93. A typical life cycle of the Indian meal moth can be completed in two weeks.

               94. The pink bollworm overwinters as a fully developed larva (fourth instar). During this period the pink bollworm is in a state of arrested development called diapause.

95 The female fall cankerworm is winged while the male is wingless.

96. The webbing clothes moth can have a very long life cycle-up to 2 years,

97. Mere contact with the saddleback moth can result in cause swelling, nausea, and leave a rash that can last for days.