Defoliator
Guides
Datana drexelii-major
Datana drexelii-major is a species of prominent moth in the family Notodontidae. The genus Datana contains multiple species of late-season defoliators that feed on hardwood trees. Larvae of Datana species are known to be gregarious feeders and can cause localized defoliation, though typically without significant long-term impacts to tree health. The specific taxonomic status and distinguishing features of D. drexelii-major relative to other Datana species require further clarification.
Datana integerrima
Walnut Caterpillar Moth
Datana integerrima, commonly known as the walnut caterpillar moth, is a North American species in the family Notodontidae. The adult moths have a wingspan of 35–50 mm and are active from May to August. The larvae are notable defoliators of walnut, hickory, and other hardwood trees, feeding gregariously in large groups. While capable of causing significant defoliation, single-season outbreaks rarely cause lasting damage to healthy trees.
Datana major
azalea caterpillar, major datana
Datana major is a moth in the family Notodontidae, commonly known as the azalea caterpillar or major datana. The species ranges across the eastern and central United States, from Maryland south to Florida and west to Kansas and Arkansas. Adults are active from June to August, with one generation per year in most of the range and a partial second generation in southern areas. The larvae are notable pests of azaleas and related ornamental plants.
Datana ministra
yellownecked caterpillar, Yellow-necked Caterpillar Moth
Datana ministra is a moth in the family Notodontidae, commonly known as the yellownecked caterpillar. The species is distributed across southern Canada and the eastern United States, extending west to California. Adults have a wingspan of approximately 42 mm and produce one generation per year. The larvae are notable defoliators of various hardwood trees.
Datana modesta
Datana modesta is a species of prominent moth in the family Notodontidae, first described by William Beutenmüller in 1890. It is native to North America and belongs to a genus whose larvae are known as generalist feeders on woody plants. The species is part of a group of late-season defoliators that typically cause minor, aesthetic damage rather than significant tree health impacts.
Datana neomexicana
Datana neomexicana is a species of prominent moth in the family Notodontidae, first described by Doll in 1911. It occurs in North America and is assigned MONA/Hodges number 7913. Like other members of the genus Datana, it is a late-season defoliator whose larvae feed on tree foliage. The species is part of a group of hardwood defoliators that typically cause minor, aesthetic damage rather than significant tree health impacts.
Datana perfusa
Large Datana
Datana perfusa is a species of prominent moth in the family Notodontidae, commonly known as the Large Datana. Described by Harrison Gray Dyar in 1923, this moth is part of a genus whose larvae are well-known defoliators of hardwood trees. The genus Datana includes several species whose caterpillars feed gregariously and are frequently documented as late-season defoliators of oaks and other hardwoods. While specific details for D. perfusa are limited, the genus is characterized by distinctive caterpillars with warning coloration and defensive behaviors.
Datana robusta
annual buttonweed, robust datana moth
Datana robusta is a species of prominent moth in the family Notodontidae, first described by Herman Strecker in 1878. It is native to North America and is commonly known as the annual buttonweed or robust datana moth. The species is assigned MONA/Hodges number 7909. Like other members of the genus Datana, it is a late-season defoliator of hardwood trees.
Diaphania hyalinata
melonworm moth, melonworm
Diaphania hyalinata, commonly known as the melonworm moth, is a crambid moth species and a significant agricultural pest of cucurbit crops. Native to the Neotropics, it has established permanent populations in the southern United States and disperses northward annually during warmer months. The species exhibits behavioral plasticity in feeding habits: in Florida and tropical regions, larvae primarily feed on leaves, while in more northern latitudes such as Virginia, they frequently burrow directly into fruits. Laboratory studies indicate a complete life cycle of approximately 20–23 days under warm conditions.
Diapheromera femorata
Northern Walkingstick, Common Walkingstick
Diapheromera femorata is the most widespread and economically significant stick insect native to the United States. Adults reach 75–95 mm in length, with females typically larger than males. The species is notable for periodic outbreak populations that can cause localized defoliation of trees, particularly oaks. It is the only phasmid of documented economic importance in North America, with historical outbreaks affecting thousands of hectares in Michigan, Wisconsin, Arkansas, and Oklahoma.
Dione juno
Juno Silverspot, Juno Longwing, Juno Heliconian
Dione juno is a heliconiine butterfly (subfamily Heliconiinae) distributed from the southern United States through Central and South America. The species is a significant agricultural pest of passion fruit (Passiflora spp.), particularly Passiflora edulis, where caterpillars can completely defoliate host plants at high population densities. Adults are characterized by orange and black dorsal wing patterns with distinctive silver spots on the ventral wing surfaces. The species has been extensively studied in Brazil and Central America for its role in agroecosystems and its diverse complex of natural enemies.
Diprion similis
Introduced Pine Sawfly, Imported Pine Sawfly, White Pine Sawfly
Diprion similis is a conifer-feeding sawfly native to central and northern Europe and Asia that has become invasive in North America following its accidental introduction around 1914. The species is notable for its arrhenotokous reproduction, where unfertilized eggs develop into male offspring, facilitating rapid population establishment. Larvae are gregarious defoliators of pine needles, with a strong preference for white pine (Pinus strobus) in North America. The species exhibits two generations per year in many regions, with second-generation larvae overwintering as prepupae in cocoons. Its invasive success has been attributed to parthenogenetic capabilities, lack of natural enemies in introduced ranges, and specialized pheromone communication involving the (2S,3R,7R)-propionate isomer of 3,7-dimethylpentadecan-2-ol.
Diprionidae
Conifer Sawflies
Diprionidae is a family of conifer-feeding sawflies comprising approximately 90-140 species across 11-13 genera. Larvae feed gregariously on conifer needles and can cause major forest outbreaks. Adults are stingless wasps with distinctive antennae: males possess pectinate (comb-like) antennae while females have serrate (saw-like) antennae with about 20 flagellomeres. The family is restricted to the Northern Hemisphere and includes significant forest pests such as Neodiprion sertifer and N. abietis.
Dryocampa
rosy maple moths
Dryocampa is a genus of small saturniid moths native to North America, containing approximately seven described species. The genus is best known for Dryocampa rubicunda, the rosy maple moth, recognized by its distinctive pink and yellow coloration. Larvae of this genus feed on maple trees (Acer species), with some species occasionally reaching outbreak densities that cause noticeable defoliation. Adults are typically nocturnal and possess reduced mouthparts, not feeding as adults.
Dryocampa rubicunda
rosy maple moth
Dryocampa rubicunda, commonly known as the rosy maple moth, is a small saturniid moth native to eastern North America. Adults are distinguished by their striking pink and yellow coloration, which varies from cream or white to bright pink or yellow. The species exhibits sexual dimorphism: males have narrower, less rounded wings and bipectinate antennae for detecting female pheromones, while females have broader wings and simple antennae. Larvae, known as greenstriped mapleworms, feed on maple leaves and can cause temporary defoliation in outbreak years.
Enargia decolor
Pale Enargia, Aspen Twoleaf Tier Moth
A noctuid moth with boreal-transcontinental distribution across North America, primarily associated with trembling aspen and related poplar species. Adults are active in late summer, with larvae capable of reaching outbreak densities that cause extensive defoliation of host stands. The species shows a disjunct western distribution pattern that may represent cryptic diversity.
Ennomos subsignaria
Elm Spanworm Moth
Ennomos subsignaria is a geometrid moth native to North America, commonly known as the elm spanworm moth. Adults have a wingspan of 35–40 mm and fly from late May to August, with one generation per year. The species is a generalist herbivore whose larvae feed on elm, apple, birch, maple, and oak. Research has documented its clumped intra-tree distribution on mature sycamore maple, with oviposition concentrated on the lower bole and larval development progressing from proximal to distal branches of the lower crown.
Epilachna
leaf-eating lady beetles, bean beetles
Epilachna is a genus of leaf-eating lady beetles in the family Coccinellidae, comprising approximately 300 species primarily distributed in the Western Hemisphere. Unlike the predominantly predatory members of Coccinellidae, Epilachna species are phytophagous, feeding on plant foliage rather than other insects. Several species are significant agricultural pests, including the Mexican bean beetle (E. varivestis) and the squash lady beetle. The genus has been subject to taxonomic revision, with some species historically placed in Epilachna now assigned to related genera such as Henosepilachna.
Erannis
Erannis is a genus of geometer moths (Geometridae: Ennominae) erected by Jacob Hübner in 1825. The genus comprises approximately twelve species distributed primarily across the Holarctic region, with greatest diversity in northern temperate zones. Several species are significant forest pests, with larvae feeding on coniferous and deciduous trees. Taxonomic placement remains debated: some authorities recognize the tribe Erannini with Erannis as type genus, while others merge this group into Boarmiini or Bistonini.
Eriocampa
woolly sawflies
Eriocampa is a small Holarctic genus of sawflies in the family Tenthredinidae comprising approximately five to ten described extant species. The genus is characterized by larvae that produce conspicuous white waxy secretions, giving them a woolly appearance that likely serves as a defense against predators and parasitoids. Several species are economically significant as defoliators of woody plants, including Eriocampa juglandis (butternut woollyworm) on walnut and hickory, and Eriocampa ovata (woolly alder sawfly) on alder. The genus has a debated taxonomic history, with various classifications placing it in different subfamilies within Tenthredinidae.
Eriocampa juglandis
Butternut Woollyworm, Butternut Woollyworm Sawfly, Butternut Wooly Worm
Eriocampa juglandis, commonly known as the butternut woollyworm, is a sawfly in the family Tenthredinidae. The larvae feed on leaves of butternut, black walnut, and hickory trees, and are notable for their distinctive white, woolly wax coating. Unlike true caterpillars, sawfly larvae possess six or more pairs of prolegs on their abdominal segments. The species has one generation per year, with larvae active in mid-summer and pupation occurring in soil over winter.
Eupareophora
spiny ash sawflies
Eupareophora is a genus of sawflies in the family Tenthredinidae, subfamily Blennocampinae. The genus contains at least two species: the West Palaearctic E. exarmata and the Nearctic E. parca. Both species are associated with ash trees (Fraxinus spp.) as hosts. Larvae are characterized by prominent spines and can cause significant defoliation. E. parca has shown rapid population increases in urban settings, suggesting potential as an urban pest.
Euproctis chrysorrhoea
Brown-tail Moth
Euproctis chrysorrhoea, the brown-tail moth, is a univoltine forest pest with a highly polyphagous larval stage. Populations exhibit phenological plasticity, with larval diapause timing and winter feeding behavior varying based on host plant foliage persistence. The species demonstrates sequential host plant utilization during mass outbreaks and shows evidence of host-associated genetic divergence. Larvae possess urticating setae that pose human health risks.
Eupseudosoma
snowy eupseudosoma (E. involutum)
Eupseudosoma is a genus of tussock moths in the family Erebidae, erected by Augustus Radcliffe Grote in 1865. The genus contains several species distributed across the Americas, with Eupseudosoma involutum (snowy eupseudosoma) being the most widespread and well-known. Some species are significant defoliators of Eucalyptus and other plants.
Eupseudosoma involuta
snowy eupseudosoma
Eupseudosoma involuta is a moth in the family Erebidae (formerly Arctiidae), commonly known as the snowy eupseudosoma. It is a defoliator species with a broad distribution across the Americas, from the southern United States through South America to Argentina, including the Caribbean islands. The species has been documented as a host for the parasitoid wasp Trichospilus diatraeae, which attacks its pupae.
Gilpinia
conifer sawflies
Gilpinia is a genus of conifer sawflies in the family Diprionidae, comprising approximately 20 described species distributed across Europe, Asia, and North America. Several species are significant forest pests, notably G. hercyniae (European spruce sawfly) and G. polytoma, which feed on spruce (Picea) species. The genus exhibits complex life history strategies including facultative diapause and variable voltinism (one to three generations annually) depending on geographic location and climate. Species identification relies heavily on morphological examination of the ovipositor, male genitalia, and wing coloration.
Gilpinia hercyniae
European Spruce Sawfly
Gilpinia hercyniae, the European spruce sawfly, is a defoliating pest of spruce trees native to Europe and introduced to North America. The species caused severe outbreaks in eastern Canada and the northeastern United States during the 1930s, with estimated timber losses of 10 million cubic metres. Populations subsequently declined due to natural viral disease and introduced biological control agents. The species exhibits arrhenotokous parthenogenesis, with males rarely encountered.
Glena
Glena is a genus of geometer moths in the family Geometridae, established by Hulst in 1896. The genus contains approximately 40 described species distributed primarily in the Americas, with documented occurrences in North America, South America, and the Caribbean. Several species have been recorded as economically significant defoliators of plantation forestry, particularly Glena bipennaria bipennaria on African mahogany (Khaya spp.) in Brazil. Host plant relationships vary among species, ranging from specialists to broader associations.
Gonipterus
Eucalyptus Weevils, Eucalyptus Snout Beetles, Eucalyptus Snout Weevils
Gonipterus is a genus of weevils in the family Curculionidae, comprising approximately 20 described species native primarily to Australia. These insects are obligate plant feeders, with many species exhibiting high host specificity. Several species, notably Gonipterus platensis, G. pulverulentus, and G. gibberus, have become significant pests of Eucalyptus plantations globally, having spread to regions where these trees have been introduced. Taxonomic confusion has historically plagued the genus, with DNA studies in 2012 clarifying that populations previously identified as G. scutellatus in New Zealand, North America, western Europe, Africa, and eastern Europe actually represent distinct species. The genus has substantial economic importance in forestry, driving research into biological control agents such as the egg parasitoid Anaphes nitens.
Gonipterus scutellatus
eucalyptus snout beetle, eucalyptus weevil, gum tree weevil
Gonipterus scutellatus is a weevil species endemic to Australia that feeds and breeds exclusively on Eucalyptus trees. It is greyish-brown with a light-colored transverse band and measures approximately 13 mm in length. The species is frequently confused with closely related weevils—G. gibberus, G. platensis, and G. pulverulentus—which share common names and were historically misidentified as G. scutellatus. Populations outside Australia previously attributed to this species have been reidentified through DNA analysis: those in New Zealand, North America, and western Europe are G. platensis, while African and eastern European populations represent an undescribed species.
Homadaula
Homadaula is a genus of small moths in the family Galacticidae, established by Lower in 1907. The genus contains approximately 15 described species distributed across Africa, Asia, and Australia. Several species are known as webworms, with larvae that construct silk webs on host foliage. Homadaula anisocentra, the mimosa webworm, is the most economically significant species and has been introduced to North America as a pest of ornamental honeylocust and mimosa trees.
Homadaula anisocentra
mimosa webworm, Mimosa Webworm Moth
Homadaula anisocentra, commonly known as the mimosa webworm, is an introduced moth species in the family Galacticidae (formerly placed in Plutellidae). Native to China, it was accidentally introduced to the United States in the 1940s and has become a significant pest of ornamental trees. The species primarily attacks mimosa (Albizia julibrissin) and honeylocust (Gleditsia triacanthos), where larvae construct silk webbing to feed on leaves. It completes two generations annually in the Mid-Atlantic region, with an additional third generation in southern states.
Hyblaea puera
teak defoliator
A small moth (wingspan 3–4 cm) and major defoliator of teak and mangrove ecosystems across tropical Asia. Adults have greyish-brown forewings that conceal brightly colored black and orange-yellow hindwings at rest. The species undergoes dramatic population outbreaks, with densities shifting from endemic levels to epidemic proportions seasonally. It has expanded beyond its native South and Southeast Asian range to Central America, Africa, and Australia, and has recently emerged as a serious invasive pest of mangroves in India and China.
Hymenomima
Hymenomima is a genus of geometrid moths described by Warren in 1895, containing approximately 28 described species distributed primarily in the Neotropical region. The genus has been subject to biological control research, with Hymenomima nr. memor evaluated and rejected as a potential agent for Brazilian peppertree due to insufficient host specificity. Species exhibit typical geometrid morphology with larvae that are leaf-feeding defoliators.
Hyphantria cunea
Fall Webworm, Fall Webworm Moth, American White Moth
The fall webworm (Hyphantria cunea) is a moth native to North America, ranging from southern Canada through the United States to northern Mexico. It is best known for its larval stage, in which caterpillars construct large silken webs on the terminal branches of host trees during late summer and fall. The species exhibits two color races that vary geographically: white moths with black-headed caterpillars predominate in northern populations, while spotted moths with red-headed caterpillars are more common in the south. Accidentally introduced to Hungary in the 1940s, it has become a destructive invasive pest across Europe and Asia, particularly in China where it is known as the 'North American White Moth.'
defoliatorweb-forming-caterpillarinvasive-speciesnative-pestpolyphagousfreeze-avoiderthermoregulationbiological-control-targethazelnut-pestmulberry-pesturban-pestornamental-pestforest-pestagricultural-pestgregarious-larvaesilken-webNorth-American-nativeEuropean-invasiveAsian-invasiveviral-biocontrolparasitoid-hosthyperparasitismIanassa lignicolor
White-streaked Prominent, white-streaked prominent moth, lacecapped caterpillar
A medium-sized moth in the family Notodontidae, commonly known as the White-streaked Prominent or lacecapped caterpillar. Adults display distinctive white streaking on the forewings. The species is widespread in eastern North America, with larvae recognized by their unique 'lace cap' appearance. The species has been subject to taxonomic revision, formerly placed in the genus Oligocentria.
Iridopsis
Iridopsis is a genus of geometrid moths (family Geometridae) established by Warren in 1894. The genus contains approximately 20 described species distributed across the Americas. Several species are economically significant as defoliators of trees, including eucalyptus pests in Brazil and native tree feeders in Chile. Host plant associations vary among species, with some showing narrow specificity and others broader feeding ranges.
Iridopsis ephyraria
Pale-winged Gray
Iridopsis ephyraria, commonly known as the pale-winged gray, is a moth species in the family Geometridae (geometer moths). First described by Francis Walker in 1860, this species occurs across eastern North America from Canada to the southern United States. The adults are active during summer months, and the larvae feed on a diverse range of woody plants.
Lambdina
Lambdina is a genus of geometrid moths comprising approximately ten described species distributed in North America. Several species are significant forest defoliators, particularly the hemlock looper (L. fiscellaria) and its subspecies, which cause economically damaging outbreaks in coniferous forests. The genus exhibits typical geometrid morphology with larvae commonly referred to as loopers due to their characteristic looping gait. Species within Lambdina can be distinguished by host associations, flight periods, and overwintering stages.
Lambdina fiscellaria
Hemlock Looper Moth, Mournful Thorn
Lambdina fiscellaria is a North American geometrid moth known as the hemlock looper or mournful thorn. It is a significant forest pest, particularly of coniferous trees, capable of causing complete defoliation and tree mortality during outbreaks. The species comprises three recognized subspecies with distinct geographic ranges and host preferences: the eastern hemlock looper (L. f. fiscellaria), western hemlock looper (L. f. lugubrosa), and western oak looper (L. f. somniaria). Adults are active from August to October with a wingspan of approximately 35 mm.
Lambdina pellucidaria
pitch pine looper, eastern pine looper, yellow-headed looper, yellow-headed looper moth
Lambdina pellucidaria is a geometrid moth found in eastern North America, commonly known as the pitch pine looper or yellow-headed looper. The species is associated with pine habitats and has been documented feeding on pitch pine, red pine, and other hard pines, as well as oak. Adults are active from March to June with regional variation, and exhibit nocturnal pheromone-mediated mating activity between midnight and 3 AM. Larvae are distinctive loopers that mine needles rather than consuming them completely, a trait that aids in identification.
Leptinotarsa decemlineata
Colorado potato beetle, Colorado beetle, ten-striped spearman, ten-lined potato beetle, potato bug
Leptinotarsa decemlineata is a major agricultural pest of potato and other solanaceous crops, causing approximately half a billion dollars in annual crop losses globally. Native to Mexico and originally associated with buffalo bur (Solanum rostratum), it shifted to potato as a host around 1860 and subsequently expanded its range across North America, Europe, and Asia. The species is notorious for its rapid evolution of resistance to insecticides, making it a model organism for studying pesticide resistance and integrated pest management strategies. Both larvae and adults feed on foliage, with the fourth instar consuming the most plant material.
Leucoma salicis
White Satin Moth, Satin Moth
Leucoma salicis is a medium-sized moth native to the Palearctic, introduced to North America in the 1920s where it became an invasive pest. Adults are distinguished by pure white wings with a silky sheen, held tent-like over the body, contrasting with striking black-and-white banded legs. Larvae feed on Salix and Populus species and can cause severe defoliation damage. The species is univoltine in most of its range, with adults active in June through August.
Lithacodes fasciola
yellow-shouldered slug, ochre-winged hag moth
Lithacodes fasciola is a small slug moth in the family Limacodidae, commonly known as the yellow-shouldered slug or ochre-winged hag moth. The species exhibits distinctive larval and adult morphology, with caterpillars showing bright yellow-green coloration with striping and adults displaying characteristic wing patterns. It has a broad distribution across eastern North America with variable voltinism depending on latitude. The larvae feed on a wide range of deciduous trees and shrubs.
Lochmaeus
Lochmaeus is a genus of moths in the family Notodontidae, first described by Edward Doubleday in 1841. The genus contains at least two species, including L. manteo and L. bilineata. Larvae are late-season defoliators of hardwood trees, with outbreaks occasionally producing conspicuous damage and abundant frass. Despite visible defoliation, impacts to tree health are generally minor.
Lochmaeus bilineata
Double-lined Prominent, double-lined prominent moth
Lochmaeus bilineata, commonly known as the double-lined prominent moth, is a notodontid moth found across eastern North America. Adults are active from spring through fall depending on latitude, with a wingspan of 32–40 mm. The larvae feed on the foliage of several hardwood tree genera including Fagus, Quercus, Tilia, Betula, and Ulmus. As a late-season defoliator, it typically causes minor, localized damage that does not threaten overall tree health.
Lochmaeus manteo
Variable Oakleaf Caterpillar Moth
Lochmaeus manteo is a moth in the family Notodontidae, commonly known as the variable oakleaf caterpillar moth. It occurs in eastern North America, where adults are active from April through October. The species is a late-season defoliator of deciduous trees, with larvae feeding primarily on Quercus (oak) species. While larval feeding can cause noticeable canopy damage and produce abundant frass, single defoliation events rarely cause significant long-term harm to tree health.
Lophocampa caryae
Hickory Tussock Moth, Hickory Halisidota, Hickory Tiger Moth
Lophocampa caryae is a tiger moth in the family Erebidae, widely distributed across eastern North America. The species has one generation per year, with adults flying in May and June. The caterpillar is covered in dense white and black hair tufts and can cause contact dermatitis in humans through its barbed setae. Despite anecdotal claims of venomous properties, no venom has been isolated; adverse reactions are characterized as irritant contact dermatitis.
Lophocampa ingens
Lophocampa ingens is a tiger moth in the family Erebidae, described by Henry Edwards in 1881. It is endemic to the southern Rocky Mountains of the United States and Mexico. Adults are active in late spring, while larvae feed on several pine species. The species is distinguished by its patterned forewings with multiple rows of white spots on a dark brown background.
Lymantria dispar
spongy moth, gypsy moth
Lymantria dispar is a forest-defoliating moth native to Europe and Asia, now invasive across multiple continents including North America. The species is notable for pronounced sexual dimorphism in adults and variable flight capability among subspecies—females of the European subspecies (L. d. dispar) are flightless, while Asian subspecies possess flight-capable females. Larvae are polyphagous and have been documented feeding on over 500 plant species. The species ranks among the world's most destructive invasive forest pests, with documented outbreaks exceeding 2.5 million caterpillars per hectare.