Gypsy Moth Outbreak

Long Island has seen a rise in the Gypsy moth caterpillar population due to the unseasonably dry spring.

In the past we’ve experienced localized outbreaks but according to Dan Gilrein, an entomologist with Cornell Cooperative, this year’s Gypsy moth presence has been the largest he recalls since 1988.

Gypsy moth caterpillar damage

Naturally occurring fungus and disease that ordinarily control the Gypsy moth grow and spread in wet environments. Because of this, Gypsy moths usually are a somewhat insignificant problem on Long Island, other than outbreaks in very localized spots. However, 2015 has been a year of peak activity due largely to a very dry May.

An infestation can leave damaged, leafless trees looking more like those of January than July. The trees can usually survive, they’re programmed to grow a second leaf covering. But that uses up much of the trees’ backup nutrients, leaving them especially susceptible to other stressors.

Gypsy moth with egg mass

The large amount of visible Gypsy moth egg sacs hanging on tree trunks, branches, and even lawn furniture are further evidence of our heavy infestation this year. Go outside and check for them, especially on oaks. They are fuzzy patches, some with a mother moth still laying. Each egg sac contains up to 1,000 eggs that will hatch next spring in time to eat the tender new leaves.
Other trees that can be affected include

  • maple
  • apple
  • aspen
  • willow
  • birch
  • mountain ash
  • pine
  • spruce

Have your trees taken
a beating?
At this point, with most of the damage already done, spraying would not be effective. Spraying should be considered for next year, though, in May and June. We are expecting another season of heavy Gypsy moth population.
If your trees have been damaged by Gypsy moth caterpillars, you may consider ourorganic fertilizer to replenish energy stores in preparation for the winter. Find more about our compost tea applications at

Contact us today for a free consultation with a NOFA-Accredited, ISA Certified Arborist.

upc-admin-usherGypsy Moth Outbreak