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Lambdina pellucidaria

Pine looper caterpillar. Photo: Connecticut Agricultural Experiment Station, Bugwood.
Scientific Name: 
Lambdina pellucidaria
Common Name: 
Pine Looper
Growing Degree Days (GDD's): 
None available at this time.
Host Plant(s) Common Name (Scientific Name): 
Pine (Pinus spp.)
Pitch pine (Pinus rigida)
Red pine (Pinus resinosa)
Shortleaf pine (Pinus echinata)
Insect Description: 

The pine looper, also known as the eastern pine looper, can at times be a serious defoliator of its host plants. Slender, dark brown pupae overwinter in the leaf litter beneath host plants. In New England, adult moths emerge by and begin to lay their oval, pale green eggs (eggs turn to yellowish-tan as they mature) in approximately May and June. Adults are mottled brown and gray in color. Heavy flights of adults may be noted in June during outbreak years. Young larvae feed by chewing notches from their host plant needles. This type of feeding leads to the needles turning straw brown. Needles browning in this manner can be a first sign of the activity of this insect. The caterpillars are also known as inchworms due to their pattern of movement. Once mature, larger caterpillars are capable of feeding on the entire needle. Fully grown caterpillars are approximately 1.2 inches long, mottled brown and gray in color, with mottled gray stripes extending down the body. The caterpillar activity increases in September and October, at which point major defoliation may occur if the population is large enough. A single generation per year is noted for this species, with outbreaks of pine looper activity historically occuring on Cape Cod in 10-year cycles. Some scientists question the separation of this species (eastern pine looper) with Lambdina athasaria, given similar flight periods of the adults and females of both species being responsive to the same sexual attractant chemicals. For now, Lambdina pellucidaria is considered to be a different species.

Damage to Host: 

The pine looper will as a young larva chew notches out of the needles of its hosts, which eventually lead to needle browning. Mature, larger caterpillars can eat the entire needle. Outbreaks occur in infrequent cycles (every 10 years) on Cape Cod, with a major outbreak in parts of eastern Massachusetts in 1994 (Robert Childs, Personal Communication). This is a native insect that is not typically a pest, although periodic outbreaks may occur.


Monitor for needle browning following egg hatch period in May and June. Heavier feeding by caterpillars may not occur until very late in the growing season. Monitor preferred hosts in areas where a cyclical population outbreak may be expected.

Cultural Management: 

No effective cultural management options are known for this native insect. 

Natural Enemies & Biological Control: 

Presumably the eastern pine looper population is managed by natural enemies such as parasitoids, predators, or pathogens. However, the details of which species impact this native insect in New England and to what extent are difficult to find. 

Chemical Management: 

Abamectin (NL)

Acephate (NL)

Acetamiprid (L)

Bacillus thuringiensis subsp. aizawai (L)

Bacillus thuringiensis subsp. kurstaki (NL)

Beauveria bassiana (NL)

Bifenthrin (NL)

Carbaryl (L)

Chlorantraniliprole (NL)

Chromobacterium subtsugae (NL)

Cyantraniliprole (NL)

Flonicamid+cyclaniliprole (N)

Horticultural oil (L)

Indoxacarb (L)

Insecticidal soap (NL)

Malathion (L)

Neem oil (NL)

Pyrethrin+sulfur (NL)

Spinosad (NL)

Tebufenozide (NL)


Active ingredients that may be applied systemically include: abamectin (injection), acephate (injection), acetamiprid (injection), chlorantraniliprole (soil drench), cyantraniliprole (soil drench, soil injection), and neem oil (soil drench).

Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.

Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.

Read and follow all label instructions for safety and proper use. If this guide contradicts language on the label, follow the most up-to-date instructions on the product label. Always confirm that the site you wish to treat and the pest you wish to manage are on the label before using any pesticide. Read the full disclaimer. Active ingredients labeled "L" indicate some products containing the active ingredient are labeled for landscape uses on trees or shrubs. Active ingredients labeled "N" indicate some products containing the active ingredient are labeled for use in nurseries. Always confirm allowable uses on product labels. This active ingredient list is based on what was registered for use in Massachusetts at the time of publication. This information changes rapidly and may not be up to date. If you are viewing this information from another state, check with your local Extension Service and State Pesticide Program for local uses and regulations. Active ingredient lists were last updated: January 2024. To check current product registrations in Massachusetts, please visit: .