112-445: L. d. dispar L. d. asiatica L. d. japonica Lymantria dispar , also known as the gypsy moth or the spongy moth , is a species of moth in the family Erebidae native to Europe and Asia . Lymantria dispar is subdivided into several subspecies, with subspecies such as L. d. dispar and L. d. japonica being clearly identifiable without ambiguity. Lymantria dispar has been introduced to several continents and
224-513: A manila folder , but may bleach out over the winter months. As the female lays them, she covers them with hair-like setae from her abdomen. Egg clusters contain from 100 to 1000 eggs. Due to the appearance of the eggs, several common names have emerged; the German Schwammspinner (literally "sponge spinner") and French la spongieuse refer to the spongy texture of the egg cluster. Larvae ( caterpillars ) emerge from egg masses in
336-598: A biological control agent in European fruit orchards. Several species of entomopathogenic nematode are important predators of insect and other invertebrate pests. Entomopathogenic nematodes form a stress–resistant stage known as the infective juvenile. These spread in the soil and infect suitable insect hosts. Upon entering the insect they move to the hemolymph where they recover from their stagnated state of development and release their bacterial symbionts . The bacterial symbionts reproduce and release toxins, which then kill
448-564: A biological control agent was made by Charles V. Riley in 1873, shipping to France the predatory mites Tyroglyphus phylloxera to help fight the grapevine phylloxera ( Daktulosphaira vitifoliae ) that was destroying grapevines in France. The United States Department of Agriculture (USDA) initiated research in classical biological control following the establishment of the Division of Entomology in 1881, with C. V. Riley as Chief. The first importation of
560-525: A few European studies cite avian predation as a large influence in keeping the gypsy moth population in control, few studies exist to prove this. Calosoma sycophanta is a beetle that preys upon the gypsy moth larvae and pupae. Larvae and adults of the species tear open their prey and feed upon them. In low density populations, there is a positive correlation between larval mortality and predation rates on pupae. Gypsy moth parasitoids have been widely studied, but they do not seem to have major effects on
672-463: A meta-analysis was done to find such an overall trend in previously published data, if it existed. In some cases floral resources are outright necessary. Overall, floral resources (and an imitation, i.e. sugar water) increase longevity and fecundity , meaning even predatory population numbers can depend on non-prey food abundance. Thus biocontrol population maintenance – and success – may depend on nearby flowers. Parasitoids lay their eggs on or in
784-514: A more frequent and severe impact on the environment. Defoliation by spongy moths triggers chemical defenses in quaking aspen , rendering them unfit host trees for Polyphemus moths , posing an additional threat to their conservation. Lymantria dispar dispar Lymantria dispar dispar , commonly known as the gypsy moth , European gypsy moth , LDD moth , or (in North America) North American gypsy moth or spongy moth ,
896-805: A natural enemy of a pest is introduced in the hope of achieving control; inductive (augmentation), in which a large population of natural enemies are administered for quick pest control; and inoculative (conservation), in which measures are taken to maintain natural enemies through regular reestablishment. Natural enemies of insects play an important part in limiting the densities of potential pests. Biological control agents such as these include predators , parasitoids , pathogens , and competitors . Biological control agents of plant diseases are most often referred to as antagonists. Biological control agents of weeds include seed predators, herbivores , and plant pathogens. Biological control can have side-effects on biodiversity through attacks on non-target species by any of
1008-732: A number of recent studies pursuing sustainable methods for controlling urban cockroaches using parasitic wasps. Since most cockroaches remain in the sewer system and sheltered areas which are inaccessible to insecticides, employing active-hunter wasps is a strategy to try and reduce their populations. Pathogenic micro-organisms include bacteria , fungi , and viruses . They kill or debilitate their host and are relatively host-specific. Various microbial insect diseases occur naturally, but may also be used as biological pesticides . When naturally occurring, these outbreaks are density-dependent in that they generally only occur as insect populations become denser. The use of pathogens against aquatic weeds
1120-461: A parasitoidal wasp into the United States was that of the braconid Cotesia glomerata in 1883–1884, imported from Europe to control the invasive cabbage white butterfly, Pieris rapae . In 1888–1889 the vedalia beetle, Novius cardinalis , a lady beetle, was introduced from Australia to California to control the cottony cushion scale, Icerya purchasi . This had become a major problem for
1232-400: A peachy fuzz that can cause serious rashes if touched by bare skin or fur. Many environmental factors such as resource availability, predator density and sexual competition are known to affect behavior from its larval stage to adult stage. A population will exist for many years in low densities. When the population enters the release phase, it rapidly expands to the outbreak phase where
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#17331043348851344-556: A replacement name through a consultative process. In January 2022, they proposed the name spongy moth , in reference to the spongy mass of the egg casing. This new common name was formally adopted in North America in March 2022. Lymantria dispar dispar is indigenous to Europe. In southeastern England, it was widespread in the 19th century, but became extinct except for occasional migrants soon after 1900. It then recolonised naturally from
1456-487: A roll of cardboard inside. Birdhouses enable insectivorous birds to nest; the most useful birds can be attracted by choosing an opening just large enough for the desired species. In cotton production, the replacement of broad-spectrum insecticides with selective control measures such as Bt cotton can create a more favorable environment for natural enemies of cotton pests due to reduced insecticide exposure risk. Such predators or parasitoids can control pests not affected by
1568-470: A sprinkling of setae . As the larval stage comes to an end they cease feeding and surround themselves in a silken net. Larvae can be distinguished from other species of caterpillar by its spots. Close to the head, five pairs of blue spots and six pairs of red spots towards its tail. This distinction will prevent confusion with the spiny elm caterpillar and other caterpillars. Eastern tent caterpillars can be distinguished by their silky tents in trees,
1680-488: A surface near where they emerged from their pupa. The eggs are covered in a coating of hairs. The covering provides protection from predators and parasites, and may be important for insulating the eggs from cold and for sealing in moisture. The larva inside the egg becomes fully developed in about one month after being laid and then enters diapause to overwinter. The egg is in the overwintering stage lasting for eight or nine months. Development ceases in preparation for
1792-612: A trained chemist and first Director of the Dominion Experimental Farms, for controlling the invasive currantworm Nematus ribesii . Between 1884 and 1908, the first Dominion Entomologist, James Fletcher, continued introductions of other parasitoids and pathogens for the control of pests in Canada. There are three basic biological pest control strategies: importation (classical biological control), augmentation and conservation. Importation or classical biological control involves
1904-497: A translation from the French name "spongieuse" for the species, referring to the sponge-like egg masses laid by L. dispar . Since the name Gypsy is widely embraced by Roma people as a self-referenced demonym in Europe, there has been no similar call to change the insect's name in its native area. The European native, and introduced North American, Lymantria dispar moths are considered to be
2016-436: A twig or tree bark, like butterfly pupae do. The males have feathery antennae versus the thin antennae of females. Size differences are also noted, with the forewing of the male moth being 20–24 millimetres ( 13 ⁄ 16 – 15 ⁄ 16 in) long, and that of the female 31–35 millimetres ( 1 + 1 ⁄ 4 – 1 + 3 ⁄ 8 in). The females are bigger than the males. Another important difference between
2128-597: A two-year period. Small, commercially-reared parasitoidal wasps , Trichogramma ostriniae , provide limited and erratic control of the European corn borer ( Ostrinia nubilalis ), a serious pest. Careful formulations of the bacterium Bacillus thuringiensis are more effective. The O. nubilalis integrated control releasing Tricogramma brassicae (egg parasitoid) and later Bacillus thuringiensis subs. kurstaki (larvicide effect) reduce pest damages more than insecticide treatments The population of Levuana iridescens ,
2240-518: A wide range of insects including caterpillars, beetle adults and larvae, and true bugs . Parasitoids are most effective at reducing pest populations when their host organisms have limited refuges to hide from them. Parasitoids are among the most widely used biological control agents. Commercially, there are two types of rearing systems: short-term daily output with high production of parasitoids per day, and long-term, low daily output systems. In most instances, production will need to be matched with
2352-533: A wide spectrum of arthropods. Entomophaga is effective against pests such as the green peach aphid . Several members of Chytridiomycota and Blastocladiomycota have been explored as agents of biological control. From Chytridiomycota, Synchytrium solstitiale is being considered as a control agent of the yellow star thistle ( Centaurea solstitialis ) in the United States. Baculoviruses are specific to individual insect host species and have been shown to be useful in biological pest control. For example,
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#17331043348852464-477: Is a species of moth in the family Erebidae . It has a native range that extends over Europe and parts of Africa, and is an invasive species in North America. Its larvae are polyphagous , consuming the leaves of over 500 species of trees, shrubs and plants. In its invasive range it is classified as a pest, notably one of the most destructive pests of hardwood trees in the Eastern United States . It
2576-461: Is a small parasitoid wasp attacking whiteflies , sap-feeding insects which can cause wilting and black sooty moulds in glasshouse vegetable and ornamental crops. It is most effective when dealing with low level infestations, giving protection over a long period of time. The wasp lays its eggs in young whitefly 'scales', turning them black as the parasite larvae pupate. Gonatocerus ashmeadi ( Hymenoptera : Mymaridae ) has been introduced to control
2688-438: Is another pathogen that is notable for its mortality. Larva killed by the pathogen have a shriveled appearance. Entomophaga maimaiga is a Japanese fungus that helps control the population of gypsy moths. It was first introduced to North America around 1910, though was not an effective control until the 1980s. Population density of larvae plays a major role in their behavior. At low density, larvae remain inactive during
2800-447: Is available to organic farmers in sachets of dried spores which are mixed with water and sprayed onto vulnerable plants such as brassicas and fruit trees . Genes from B. thuringiensis have also been incorporated into transgenic crops , making the plants express some of the bacterium's toxins, which are proteins . These confer resistance to insect pests and thus reduce the necessity for pesticide use. If pests develop resistance to
2912-447: Is derived from the Latin for "unequal" and it depicts the differing characteristics between the sexes. For the purposes of taxonomy, the common names European gypsy moth and North American gypsy moth represent the same subspecies, Lymantria dispar dispar , as opposed to subspecies of L. dispar from Asia. Confusion over the species and subspecies is widespread. For regulatory purposes,
3024-466: Is designated the nominate subspecies of Lymantria dispar . The species L. dispar has been split into several subspecies, including L. d. subsp. asiatica and L. d. subsp. japonica . The family is Erebidae, subfamily Lymantriinae. Lymantriid larvae are commonly called tussock moths because of the tufts of hair on the larvae. The name Lymantria dispar is composed of two Latin-derived words. Lymantria means "destroyer". The word dispar
3136-677: Is effective against white flies, thrips and aphids; Purpureocillium lilacinus is used against root-knot nematodes , and 89 Trichoderma species against certain plant pathogens. Trichoderma viride has been used against Dutch elm disease , and has shown some effect in suppressing silver leaf , a disease of stone fruits caused by the pathogenic fungus Chondrostereum purpureum . Pathogenic fungi may be controlled by other fungi, or bacteria or yeasts, such as: Gliocladium spp., mycoparasitic Pythium spp., binucleate types of Rhizoctonia spp., and Laetisaria spp. The fungi Cordyceps and Metacordyceps are deployed against
3248-542: Is frequently released inundatively to control harmful moths. New way for inundative releases are now introduced i.e. use of drones. Egg parasitoids are able to find the eggs of the target host by means of several cues. Kairomones were found on moth scales. Similarly, Bacillus thuringiensis and other microbial insecticides are used in large enough quantities for a rapid effect. Recommended release rates for Trichogramma in vegetable or field crops range from 5,000 to 200,000 per acre (1 to 50 per square metre) per week according to
3360-475: Is greatest if the agent has temporal persistence so that it can maintain its population even in the temporary absence of the target species, and if it is an opportunistic forager, enabling it to rapidly exploit a pest population. One of the earliest successes was in controlling Icerya purchasi (cottony cushion scale) in Australia, using a predatory insect Rodolia cardinalis (the vedalia beetle). This success
3472-400: Is lethal. Egg deposits that are low or on the ground can be insulated against temperatures, including snow, and survive the lethal temperatures. Temperatures above 32 °C (90 °F) increase growth and development. Rainfall can drown larvae before they are established; low populations are correlated to heavy rainfall during the larval stage. Wind is also critical to the dispersal of
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3584-460: Is listed as one of the 100 most destructive invasive species worldwide. Carl Linnaeus first described the species as Phalaena [ Bombyx ] dispar in 1758. The subject of classification has changed throughout the years, resulting in confusion surrounding the species' taxonomy . This caused many references to describe this one species in different ways. The family has jumped between Lymantriidae, Noctuidae and Erebidae. Lymantria dispar dispar
3696-603: Is native to temperate forests in western Europe . It had been introduced to the United States in 1869, and to Canada in 1912. The Asian subspecies ( Lymantria dispar asiatica ) is native to temperate Asia east of the Ural mountains. Since the early 1990s it has also been detected along the West Coast of temperate North America. From Southern Europe it is spreading northwards into Germany and other countries, where it hybridizes with
3808-462: Is now additionally found as an invasive species in Africa , North America and South America . The polyphagous larvae live on a variety of deciduous and coniferous trees and can cause severe damage in years of mass reproduction. Due to these features, Lymantria dispar is listed among the world's 100 worst invasive alien species . The etymology of “gypsy moth” is not conclusively known; however,
3920-526: The Bt protein . Reduced prey quality and abundance associated with increased control from Bt cotton can also indirectly decrease natural enemy populations in some cases, but the percentage of pests eaten or parasitized in Bt and non-Bt cotton are often similar. Predators are mainly free-living species that directly consume a large number of prey during their whole lifetime. Given that many major crop pests are insects, many of
4032-458: The Lymantria dispar multicapsid nuclear polyhedrosis virus has been used to spray large areas of forest in North America where larvae of the spongy moth are causing serious defoliation. The moth larvae are killed by the virus they have eaten and die, the disintegrating cadavers leaving virus particles on the foliage to infect other larvae. A mammalian virus, the rabbit haemorrhagic disease virus
4144-526: The Northeast and Midwest of the United States was reported by Scientific American . These regions were experiencing one of the most severe outbreaks ever recorded, with some areas reporting densities exceeding 2,500,000 caterpillars per hectare (1,000,000 per acre), and certain regions have been grappling with this issue for five consecutive years. Since the introduction of the species to North America, spongy moths have caused significant ecological damage. Over
4256-582: The glassy-winged sharpshooter Homalodisca vitripennis (Hemiptera: Cicadellidae ) in French Polynesia and has successfully controlled ~95% of the pest density. The eastern spruce budworm is an example of a destructive insect in fir and spruce forests. Birds are a natural form of biological control, but the Trichogramma minutum , a species of parasitic wasp, has been investigated as an alternative to more controversial chemical controls. There are
4368-524: The sexual dimorphism observed in the male and female imagines . In July 2021 the Entomological Society of America decided to remove the name "gypsy moth" from its Common Names of Insects and Related Organisms List as "hurtful to the Romani people ", since gypsy is considered an ethnic slur by some Romany people in North America. In January 2022, the new common name "spongy moth" was proposed, as
4480-502: The tachinids Parasetigena silvestris , which may have contributed in prevention of further increase in L. dispar in this locality. Gypsy moth populations in different locations show vulnerability to different viral species . Nuclear polyhedrosis virus caused significant mortality in some cases. The most important pathogen is the Lymantria dispar multicapsid nuclear polyhedrosis virus (LdMNPV), sometimes referred to as NPV or Borralinivirus reprimens . Viral particles consumed by
4592-417: The white-footed mouse or Anastaus disparis , have a significant impact on the population dynamics of the moth. On the other hand, avian predation and invertebrate predation show only small effects on population dynamics. The white-footed mouse , Peromyscus leucopus , is considered important for regulating sparse moth populations. Rodents consume larvae and pupae that seek resting sites near or on
Lymantria dispar - Misplaced Pages Continue
4704-470: The 1980s, the differences were already notable. As noted in The Gypsy Moth (1896) by Forbush and Fernald , the moth was considered a nuisance just ten years after their release. The first major outbreak occurred in 1889, and Forbush and Fernald recount the extent of devastation: all the trees being defoliated and caterpillars covering houses and sidewalks and raining down upon residents. At first it
4816-651: The 1990s; colonies were found in London from 1995 and Buckinghamshire from 2005, and more widely since. Lymantria dispar dispar was first brought to North America in 1869 and rapidly became an invasive species . Étienne Léopold Trouvelot imported the moths with the intent of interbreeding them with silk moths in order to establish a new silkworm industry in the West. The moths were accidentally released from his residence in Medford, Massachusetts . There are conflicting reports on
4928-458: The Colombian cities of Bello , Medellín , and Itagüí . The project was executed by non-profit World Mosquito Program (WMP). Wolbachia prevents mosquitos from transmitting viruses such as dengue and zika . The insects pass the bacteria on to their offspring. The project covered a combined area of 135 square kilometres (52 sq mi), home to 3.3 million people. Most of the project area reached
5040-585: The European spongy moth, L. d. dispar . A colony had been reported from Great Britain in 1995. Lymantria dispar was accidentally introduced into North America by artist and astronomer Étienne Léopold Trouvelot in 1869, who imported it from Europe while looking for a source of silk to replace the shortage of cotton caused by the American Civil War. Afterwards, several species of parasitoids and predators have been introduced as biological control agents in attempts to help control this moth. Beginning in
5152-500: The Levuana moth, a serious coconut pest in Fiji , was brought under control by a classical biological control program in the 1920s. Augmentation involves the supplemental release of natural enemies that occur in a particular area, boosting the naturally occurring populations there. In inoculative release, small numbers of the control agents are released at intervals to allow them to reproduce, in
5264-472: The U. S. Department of Agriculture has defined Asian Gypsy Moth as "any biotype of Lymantria dispar ( sensu lato ) possessing female flight capability". despite Lymantria dispar asiatica not being the only classified subspecies that is capable of flight; even females of L. d. dispar can fly, if only very weakly. Traditionally, all L. dispar have been referred to as gypsy moth, including when referring to Japanese, Indian, and Asiatic subspecies. In
5376-654: The above mechanisms, especially when a species is introduced without a thorough understanding of the possible consequences. The term "biological control" was first used by Harry Scott Smith at the 1919 meeting of the Pacific Slope Branch of the American Association of Economic Entomologists, in Riverside, California . It was brought into more widespread use by the entomologist Paul H. DeBach (1914–1993) who worked on citrus crop pests throughout his life. However,
5488-457: The amount of land covered by the plant. Another aquatic weed, the giant salvinia ( Salvinia molesta ) is a serious pest, covering waterways, reducing water flow and harming native species. Control with the salvinia weevil ( Cyrtobagous salviniae ) and the salvinia stem-borer moth ( Samea multiplicalis ) is effective in warm climates, and in Zimbabwe, a 99% control of the weed was obtained over
5600-562: The appropriate release dates when susceptible host species at a suitable phase of development will be available. Larger production facilities produce on a yearlong basis, whereas some facilities produce only seasonally. Rearing facilities are usually a significant distance from where the agents are to be used in the field, and transporting the parasitoids from the point of production to the point of use can pose problems. Shipping conditions can be too hot, and even vibrations from planes or trucks can adversely affect parasitoids. Encarsia formosa
5712-579: The attracting pheromone after mating. After mating, the females begin depositing the eggs. Adult moths live about one week. They do not possess an active digestive system and cannot feed, but they can drink in moisture. The reproductive chance for females lasts about two days, with the pheromone for attracting males being diminished by the third day. Due to the pheromone's potency, most females will mate. Females lay their eggs on trees, shrubs, rocks, vehicles, and plants of many types. Each of them typically lays about 500 eggs. The eggs are covered with
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#17331043348855824-671: The autumn allow insects to make use of their hollow stems during winter. In California, prune trees are sometimes planted in grape vineyards to provide an improved overwintering habitat or refuge for a key grape pest parasitoid. The providing of artificial shelters in the form of wooden caskets, boxes or flowerpots is also sometimes undertaken, particularly in gardens, to make a cropped area more attractive to natural enemies. For example, earwigs are natural predators that can be encouraged in gardens by hanging upside-down flowerpots filled with straw or wood wool . Green lacewings can be encouraged by using plastic bottles with an open bottom and
5936-509: The body of an insect host, which is then used as a food for developing larvae. The host is ultimately killed. Most insect parasitoids are wasps or flies , and many have a very narrow host range. The most important groups are the ichneumonid wasps , which mainly use caterpillars as hosts; braconid wasps , which attack caterpillars and a wide range of other insects including aphids; chalcidoid wasps , which parasitize eggs and larvae of many insect species; and tachinid flies , which parasitize
6048-716: The book Guangdong Xing Yu (17th century), Lingnan by Wu Zhen Fang (Qing dynasty), in Nanyue Miscellanies by Li Diao Yuan, and others. Biological control techniques as we know them today started to emerge in the 1870s. During this decade, in the US, the Missouri State Entomologist C. V. Riley and the Illinois State Entomologist W. LeBaron began within-state redistribution of parasitoids to control crop pests. The first international shipment of an insect as
6160-477: The borders of rice fields. These provide nectar to support parasitoids and predators of planthopper pests and have been demonstrated to be so effective (reducing pest densities by 10- or even 100-fold) that farmers sprayed 70% less insecticides and enjoyed yields boosted by 5%. Predators of aphids were similarly found to be present in tussock grasses by field boundary hedges in England, but they spread too slowly to reach
6272-403: The brown-tail moth, Euproctis chrysorrhoea , invasive pests of trees and shrubs. As a result, nine parasitoids (solitary wasps) of the spongy moth, seven of the brown-tail moth, and two predators of both moths became established in the US. Although the spongy moth was not fully controlled by these natural enemies, the frequency, duration, and severity of its outbreaks were reduced and the program
6384-453: The centers of fields. Control was improved by planting a meter-wide strip of tussock grasses in field centers, enabling aphid predators to overwinter there. Cropping systems can be modified to favor natural enemies, a practice sometimes referred to as habitat manipulation. Providing a suitable habitat, such as a shelterbelt , hedgerow , or beetle bank where beneficial insects such as parasitoidal wasps can live and reproduce, can help ensure
6496-402: The day, but in high populations become hyperactive. Interbreeding produces deleterious genetic effects, and dispersal serves to reduce this effect. Temperature is important to the gypsy moth. Low temperatures are fatal. Temperatures of −9 °C (16 °F) can be withstood during the winter, an extended period will kill the larvae inside and −23 °C (−9 °F) even for a short time
6608-595: The decades since, the same biocontrol methods that are routine on land have become common in the water. Bacteria used for biological control infect insects via their digestive tracts, so they offer only limited options for controlling insects with sucking mouth parts such as aphids and scale insects. Bacillus thuringiensis , a soil-dwelling bacterium, is the most widely applied species of bacteria used for biological control, with at least four sub-species used against Lepidopteran ( moth , butterfly ), Coleopteran (beetle) and Dipteran (true fly) insect pests. The bacterium
6720-782: The eastern US, the gypsy moth prefers leaves of oaks, aspen , apple , sweetgum , speckled alder , basswood , gray birch , paper birch , poplar , willow , and hawthorns , among other species. Older larvae feed on several species of softwood that younger larvae avoid, including cottonwood , hemlock , Atlantic white cypress , and pine and spruce species native to the east. The gypsy moth avoids ash trees , tulip-tree , American sycamore , butternut , black walnut , catalpa , flowering dogwood , balsam fir , arborvitae , American holly , and mountain laurel and rhododendron shrubs, but will feed on these in late instars when densities are extremely high. Many species have been identified as preying on L. dispar . Some species, such as
6832-431: The effectiveness of barn owls for this purpose, they are known rodent predators that can be used in addition to or instead of cats; they can be encouraged into an area with nest boxes. In Honduras, where the mosquito Aedes aegypti was transmitting dengue fever and other infectious diseases, biological control was attempted by a community action plan; copepods , baby turtles , and juvenile tilapia were added to
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#17331043348856944-429: The egg and the fly larva will hatch inside its gut. Eight species of parasitic wasps attack the gypsy moth. Ooencyrtus kuvanae and Anastatus disparis attack the eggs. O. kuvanae attacks the eggs, but the effectiveness is limited by the ovipositor which can only penetrate the surface layer of the egg cluster. A. disparis has limited success as a predator because it can only attack unembroyonated eggs and
7056-457: The female wasps do not have wings. Even so, A. disparis is the only species that is known to occasionally affect the population dynamics of the gypsy moth. Apanteles melanoscelus and Phobocampe disparis parasitize the early larva stages. intermedia and Monodontomerus aureus parasitize the gypsy moth pupae. A parasite native to North America, Itoplectes conquisitor , attacks and kills gypsy moth pupae, but development of
7168-436: The ground, and in other places where larvae rested. During periods when population numbers are dense, pupation is not restricted to these locations, but can take place in sheltered and open locations, even exposed on the trunks of trees or on foliage of nonhost trees. Usually, the caterpillars create flimsy cocoons made of silk strands holding the leaf together, while others do not cover their pupae in cocoons, but rather hang from
7280-684: The ground. The white-footed mouse is the most common and widely distributed small mammal in the northeastern United States. The northern short-tailed shrew is common east of the Rocky Mountains and will consume the larva and pupa. Insectivorous birds prey upon the larva of the gypsy moth, but the egg clusters are protected by their hair coverings. The effects of bird predation have not been fully studied in North America, but it has been well documented in Japan and Eurasia. When outbreaks of gypsy moths occur, bird predation has no significant effect on
7392-403: The history of pheromone chemistry. Courtship is not elaborate: the female must raise her wing to allow the male to couple with her. The moths remain in copula for up to an hour, but the transfer of the spermatophore is usually accomplished within 10 minutes. A male moth can inseminate more than one female. Multiple mating in females is possible but uncommon, as the female stops releasing
7504-400: The hope of setting up longer-term control and thus keeping the pest down to a low level, constituting prevention rather than cure. In inundative release, in contrast, large numbers are released in the hope of rapidly reducing a damaging pest population, correcting a problem that has already arisen. Augmentation can be effective, but is not guaranteed to work, and depends on the precise details of
7616-403: The host insect. Phasmarhabditis hermaphrodita is a microscopic nematode that kills slugs. Its complex life cycle includes a free-living, infective stage in the soil where it becomes associated with a pathogenic bacteria such as Moraxella osloensis . The nematode enters the slug through the posterior mantle region, thereafter feeding and reproducing inside, but it is the bacteria that kill
7728-414: The interactions between each pest and control agent. An example of inoculative release occurs in the horticultural production of several crops in greenhouses . Periodic releases of the parasitoidal wasp, Encarsia formosa , are used to control greenhouse whitefly , while the predatory mite Phytoseiulus persimilis is used for control of the two-spotted spider mite. The egg parasite Trichogramma
7840-409: The introduction of a pest's natural enemies to a new locale where they do not occur naturally. Early instances were often unofficial and not based on research, and some introduced species became serious pests themselves. To be most effective at controlling a pest, a biological control agent requires a colonizing ability which allows it to keep pace with changes to the habitat in space and time. Control
7952-462: The large moth species previously abundant in the Northeast. Another is the encyrtid wasp Ooencyrtus kuvanae which attacks L. dispar eggs but is not strictly host specific, and also parasitizes the eggs of other Lepidoptera species. The most effective control agents are microbial pathogens: a virus ( LdmNPV ), and a fungus ( Entomophaga maimaiga ). In June 2024, the severity of the outbreak in
8064-485: The larva is rare within the host and the number of attacks themselves is also low. Glyptapanteles portheriae and G. liparidis are both wasps that lay eggs on the gypsy moth larva. Study of G. liparidis showed almost 90% success when the host is parasitized during premolt to the third instar. Most invertebrate predation occurred when larvae were in the litter. The population in Austria suffered high parasitism by
8176-404: The larva when eating through the egg chorion will kill them during the first instar. The bodies disintegrate, spreading the virus on the foliage, which will then be consumed by other larvae. Outbreaks of the virus result in high larva mortality, and the odor of the decaying larvae permeates the area. The pathogen is used as an insecticide under the name Gypchek . Streptococcus faecalis
8288-665: The larvae. Wind speeds of several miles per hour are enough to break the silk threads and disperse the larvae. Biological control Biological control or biocontrol is a method of controlling pests , whether pest animals such as insects and mites , weeds , or pathogens affecting animals or plants by using other organisms . It relies on predation , parasitism , herbivory , or other natural mechanisms, but typically also involves an active human management role. It can be an important component of integrated pest management (IPM) programs. There are three basic strategies for biological control: classical (importation), where
8400-471: The late 1800s, at least ten species were established this way, but for nearly a century, there was little regulation or research on the effectiveness or non-target effects of these introduced natural enemies. Several were generalists that offered little control of L. dispar and attacked other native insects. One such species is the tachinid fly Compsilura concinnata , which attacked many other host species (over 180 known hosts documented), decimating many of
8512-406: The leaf hairs and then move onto the leaf epidermis. Feeding occurs in the daytime, primarily in the morning and late afternoon. As the larva grow, the feeding becomes a nocturnal activity. When not eating, the larva will remain on the underside of the leaf and make a mat of silk for attachment. To grow, the larva must molt . Larvae are characterized by the term instar , which refers to
8624-511: The level of pest infestation. Similarly, nematodes that kill insects (that are entomopathogenic) are released at rates of millions and even billions per acre for control of certain soil-dwelling insect pests. The conservation of existing natural enemies in an environment is the third method of biological pest control. Natural enemies are already adapted to the habitat and to the target pest, and their conservation can be simple and cost-effective, as when nectar-producing crop plants are grown in
8736-466: The males are typically nocturnal , but can sometimes be seen flying during the day as well. The males fly up and down tree trunks, or other vertical objects in search of females. When heavy, black-and-white egg-laden females emerge, they emit a pheromone that attracts the males. The female has a small gland near the tip of the abdomen that releases the pheromone with a pumping motion, termed "calling". It can attract males from long distances, tracking
8848-563: The moth strictly consumes its host plant, poison hemlock, and can exist at hundreds of larvae per individual host plant, destroying large swathes of the hemlock. For rodent pests , cats are effective biological control when used in conjunction with reduction of "harborage"/hiding locations. While cats are effective at preventing rodent "population explosions" , they are not effective for eliminating pre-existing severe infestations. Barn owls are also sometimes used as biological rodent control. Although there are no quantitative studies of
8960-520: The newly developed citrus industry in California, but by the end of 1889, the cottony cushion scale population had already declined. This great success led to further introductions of beneficial insects into the US. In 1905 the USDA initiated its first large-scale biological control program, sending entomologists to Europe and Japan to look for natural enemies of the spongy moth, Lymantria dispar dispar , and
9072-600: The number of times a larva has molted; a first-instar larva has not yet molted, a second instar has molted once, a third instar twice, etc. Males typically are five instars and females are six instars. When the larvae reach the fourth instar, they become nocturnal feeders, and will return to their resting places at dawn, hiding under flaps of bark, in crevices, or under branches - any place that provides protection. Newly hatched larvae are black with long, hair-like setae. Older larvae have five pairs of raised blue spots and six pairs of raised brick-red spots along their backs, and
9184-457: The past century, their range has expanded at an average rate of 21 km (13 mi) per year, resulting in the cumulative defoliation of 33,000,000 ha (82,000,000 acres) of forest between 1970 and 2013. The U.S. Forest Service allocates an average annual budget of $ 30 million toward control efforts. However, climate change has contributed to the prolongation of outbreak cycles, which typically occur every eight to twelve years. This has led to
9296-543: The population of weevils in the alfalfa area treated for alfalfa weevil in the Northeastern United States remained 75 percent down. Alligator weed was introduced to the United States from South America . It takes root in shallow water, interfering with navigation , irrigation , and flood control . The alligator weed flea beetle and two other biological controls were released in Florida , greatly reducing
9408-706: The population size will rise several orders of magnitude and fall back within only a few generations. The gypsy moth brings one of the largest impacts in defoliation of deciduous trees in the Northern Hemisphere. Since its introduction into the United States in 1868 or 1869, it has spread both west and south, now taking over most of the hardwood forests in the eastern United States and Canada. Over three hundred species of trees and shrubs are hosts. Larvae will climb up any object in their path in search of food. Larvae prefer oak trees, but may feed on many species of trees and shrubs, both hardwood and conifer. In
9520-414: The population. Birds that consume gypsy moth larvae, pupae and adults include the blue jay , red-eyed vireo , eastern towhee , northern oriole , catbird and the European robin . The black-capped chickadee feeds on the moth throughout its entire life cycle, including the eggs. Many bird species feed on gypsy moth larvae, but they are not a major food source for any common bird species. Although
9632-441: The population. Four species of parasitic flies prey on gypsy moth larva. Parasetigana silvestris and Exorista larvarum lay an egg on the gypsy moth larva. If that egg hatches before the gypsy moth larva molts, the fly larva will penetrate the host. Compsilura concinnata pierces the gypsy moth larva and deposits its own larva inside. Blepharipa pratensis lays its eggs on leaves. The gypsy moth larva will consume
9744-486: The practice has previously been used for centuries. The first report of the use of an insect species to control an insect pest comes from " Nanfang Caomu Zhuang " (南方草木狀 Plants of the Southern Regions ) ( c. 304 AD ), attributed to Western Jin dynasty botanist Ji Han (嵇含, 263–307), in which it is mentioned that " Jiaozhi people sell ants and their nests attached to twigs looking like thin cotton envelopes,
9856-768: The predators used in biological control are insectivorous species. Lady beetles , and in particular their larvae which are active between May and July in the northern hemisphere, are voracious predators of aphids , and also consume mites , scale insects and small caterpillars . The spotted lady beetle ( Coleomegilla maculata ) is also able to feed on the eggs and larvae of the Colorado potato beetle ( Leptinotarsa decemlineata ). The larvae of many hoverfly species principally feed upon aphids , one larva devouring up to 400 in its lifetime. Their effectiveness in commercial crops has not been studied. The running crab spider Philodromus cespitum also prey heavily on aphids, and act as
9968-526: The predatory midge Feltiella acarisuga , and a ladybird Stethorus punctillum . The bug Orius insidiosus has been successfully used against the two-spotted spider mite and the western flower thrips ( Frankliniella occidentalis ). Predators including Cactoblastis cactorum (mentioned above) can also be used to destroy invasive plant species. As another example, the poison hemlock moth ( Agonopterix alstroemeriana) can be used to control poison hemlock ( Conium maculatum ). During its larval stage,
10080-444: The presence of a back stripe, and their preference for cherry trees. The larvae reach maturity between mid-June and early July, then enter the pupal stage, during which larvae change into adult moths. Pupation lasts from 14–17 days. The adult moth will emerge, fully developed, by splitting the pupal skin. When the population is spread out and running low, pupation can take place under flaps of bark, in crevices, under branches, on
10192-558: The reddish-yellow ant being larger than normal. Without such ants, southern citrus fruits will be severely insect-damaged ". The ants used are known as huang gan ( huang = yellow, gan = citrus) ants ( Oecophylla smaragdina ). The practice was later reported by Ling Biao Lu Yi (late Tang dynasty or Early Five Dynasties ), in Ji Le Pian by Zhuang Jisu ( Southern Song dynasty ), in the Book of Tree Planting by Yu Zhen Mu ( Ming dynasty ), in
10304-548: The resulting actions. One states that despite issuing oral and written warnings of possible consequences, no officials were willing to assist in searching out and destroying the moths. The other notes that Trouvelot was, in fact, well aware of the risk and there is no direct evidence that he contacted any government officials about the moths' release. Though the Asiatic and the Eurasian moths were not classified as different subspecies in
10416-571: The same subspecies, Lymantria dispar dispar . Confusion over the classification of species and subspecies exists. The U. S. Department of Agriculture defines the Asian subspecies as "any biotype of L. dispar possessing female flight capability", despite L. d. asiatica not being the only accepted subspecies that is capable of flight. Traditionally, L. dispar has been referred to as "gypsy moth" even when referring to Japanese, Indian and Asiatic populations. The European subspecies ( Lymantria dispar dispar )
10528-403: The scent through its erratic flight pattern. The sex pheromone of female gypsy moths is (7 R ,8 S )-7,8-epoxy-2-methyloctadecane. A previous failed identification of this pheromone, 10-acetoxy- cis -7-hexadec-1-ol, was given the trivial name of gyptol. It was found in female moth extracts, but was later shown to be inactive. The structure determination of this pheromone was an eventful chapter in
10640-533: The sexes is that females possess fully formed wings but do not fly. Female flight is common in Eurasia, but these moths may be of a different species. Moths usually emerge from pupae in July, but it can vary with population density and climate. The brown male gypsy moth emerges first, usually one or two days before the females do. The males fly in rapid zigzag patterns, but are capable of direct flight. Like most moths,
10752-469: The slug. The nematode is available commercially in Europe and is applied by watering onto moist soil. Entomopathogenic nematodes have a limited shelf life because of their limited resistance to high temperature and dry conditions. The type of soil they are applied to may also limit their effectiveness. Species used to control spider mites include the predatory mites Phytoseiulus persimilis , Neoseilus californicus , and Amblyseius cucumeris ,
10864-563: The species' native area, the English common name is (and remains) gypsy moth. In North America in July 2021, the Entomological Society of America announced it was delisting the common name gypsy moth as part of an effort to replace racist or otherwise offensive names, as Gypsy is considered an offensive slur by some in the North American Romani community . This led the Society to select
10976-680: The spread of the plant, the cactus moth Cactoblastis cactorum , and the scale insect Dactylopius . Between 1926 and 1931, tens of millions of cactus moth eggs were distributed around Queensland with great success, and by 1932, most areas of prickly pear had been destroyed. The first reported case of a classical biological control attempt in Canada involves the parasitoidal wasp Trichogramma minutum . Individuals were caught in New York State and released in Ontario gardens in 1882 by William Saunders,
11088-546: The spread, hypothesizing that strong easterly winds carried larvae across Lake Michigan to Wisconsin, a distance of at least 50 miles (80 km). Firewood transport is a common way for the eggs to spread, since the moths will lay their eggs on dead wood. Attempts have been made to limit the movement of firewood to reduce the moth's spread. Egg masses are typically laid on branches and trunks of trees, but may be found in any sheltered location, including rocks, foliage and vehicles. Females are flightless, so they lay eggs on
11200-560: The spring. Most larvae hatch within a week, but can take as long as a month. The new larvae remain on or near the egg cluster if they hatch in rainy weather or if the temperature is below 7 °C (45 °F). The larvae will disperse even if there is enough foliage for growth, hanging from silk threads and waiting for the wind to send them aloft. The larvae are about 3 millimetres ( 1 ⁄ 8 in) long when they first hatch and will grow to 50 to 90 millimetres (2 to 3 + 1 ⁄ 2 in). The larva will first feed on
11312-466: The survival of populations of natural enemies. Things as simple as leaving a layer of fallen leaves or mulch in place provides a suitable food source for worms and provides a shelter for insects, in turn being a food source for such beneficial mammals as hedgehogs and shrews . Compost piles and stacks of wood can provide shelter for invertebrates and small mammals. Long grass and ponds support amphibians. Not removing dead annuals and non-hardy plants in
11424-579: The target of infecting 60% of local mosquitoes. The technique is not endorsed by WHO. Entomopathogenic fungi , which cause disease in insects, include at least 14 species that attack aphids . Beauveria bassiana is mass-produced and used to manage a wide variety of insect pests including whiteflies , thrips , aphids and weevils . Lecanicillium spp. are deployed against white flies, thrips and aphids. Metarhizium spp. are used against pests including beetles, locusts and other grasshoppers, Hemiptera , and spider mites . Paecilomyces fumosoroseus
11536-402: The term is known to have been in use (as 'Gipsey') as early as 1832. Moths of the subfamily Lymantriinae are commonly called tussock moths due to the tussock-like tufts of hair on the caterpillars . The name Lymantria dispar is composed of two Latin-derived words. The generic name Lymantria means 'destroyer'. The species epithet dispar means 'to separate' in Latin; it refers to
11648-578: The toxins in these crops, B. thuringiensis will become useless in organic farming also. The bacterium Paenibacillus popilliae which causes milky spore disease has been found useful in the control of Japanese beetle , killing the larvae. It is very specific to its host species and is harmless to vertebrates and other invertebrates. Bacillus spp., fluorescent Pseudomonads , and Streptomycetes are controls of various fungal pathogens. The largest-ever deployment of Wolbachia -infected A. aegypti mosquitoes reduced dengue incidence by 94–97% in
11760-491: The wells and tanks where the mosquito breeds and the mosquito larvae were eliminated. Even amongst arthropods usually thought of as obligate predators of animals (especially other arthropods), floral food sources ( nectar and to a lesser degree pollen ) are often useful adjunct sources. It had been noticed in one study that adult Adalia bipunctata (predator and common biocontrol of Ephestia kuehniella ) could survive on flowers but never completed its life cycle , so
11872-618: The wind. The larvae spin silken threads and hang from them, waiting for the wind to blow. The light larvae have long hairs that increase their surface area, which are suitable for being carried aloft. The natural spread is slow, but transportation of the moth has led to isolated populations, with accidental transport of the eggs being noted. According to the United States Department of Agriculture, without intervention, this pest spreads about 13 miles (21 km) per year. A study published in 2012 suggests that storms can accelerate
11984-541: The winter. After an acclimation stage, during which the larva inside the egg reduces its water content, eggs can withstand freezing temperatures. The larva inside the egg resumes activity in the spring, and reabsorbs water. The larva will then chew through the chorion of the egg and the protective hair of the egg cluster in the spring. Egg clusters are usually an oval about 19 millimetres ( 3 ⁄ 4 in) wide and 38 millimetres ( 1 + 1 ⁄ 2 in) long. The egg masses are buff yellow-brown, likened to
12096-400: Was introduced to Australia to attempt to control the European rabbit populations there. It escaped from quarantine and spread across the country, killing large numbers of rabbits. Very young animals survived, passing immunity to their offspring in due course and eventually producing a virus-resistant population. Introduction into New Zealand in the 1990s was similarly successful at first, but
12208-514: Was regarded as successful. This program also led to the development of many concepts, principles, and procedures for the implementation of biological control programs. Prickly pear cacti were introduced into Queensland , Australia as ornamental plants, starting in 1788. They quickly spread to cover over 25 million hectares of Australia by 1920, increasing by 1 million hectares per year. Digging, burning, and crushing all proved ineffective. Two control agents were introduced to help control
12320-456: Was repeated in California using the beetle and a parasitoidal fly, Cryptochaetum iceryae . Other successful cases include the control of Antonina graminis in Texas by Neodusmetia sangwani in the 1960s. Damage from Hypera postica , the alfalfa weevil, a serious introduced pest of forage, was substantially reduced by the introduction of natural enemies. 20 years after their introduction
12432-472: Was uncertain what species was responsible for the outbreak, but after the caterpillar was identified by entomologist Maria Elizabeth Fernald , an eradication program began in 1890. Eventually they would reach the Pacific Northwest , sporadically invading but so far not becoming established there, due to successful eradication campaigns. The small larvae of the moth take to the air and are carried by
12544-445: Was unknown until a groundbreaking 1972 proposal by Zettler and Freeman. Up to that point biocontrol of any kind had not been used against any water weeds. In their review of the possibilities, they noted the lack of interest and information thus far, and listed what was known of pests-of-pests – whether pathogens or not. They proposed that this should be relatively straightfoward to apply in the same way as other biocontrols. And indeed in
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