Gypsy Moths & Tent Caterpillars

Gypsy moths & tent caterpillars can do serious damage to ornamental & shade trees in our area. They are active in the early spring and similar in appearance. They are often confused with each other, but the controls are the same for both.

GYPSY MOTHS

Gypsy moth larvae feed on the foliage of host plants in April to May for seven to eight weeks. They hide in shady places during the day and begin to feed at night. On heavily infested trees, they may feed during the day. Gypsy moth larvae are very hairy, with two rows of blue dots on the first third of their bodies and red dots on the last two thirds. They can grow up to 2 inches.
Most trees can withstand one or two consecutive years of defoliation before severe decline or death. Needle evergreens may die after one complete defoliation because they are unable to replenish all their needles.

Hosts

Apple, Alder, Basswood, Hawthorn, Hemlock, Oak, Pine, River Birch, Spruce, Willow

Less Common Hosts

Black Birch, Paper Birch, Yellow Birch, Black Gum, Cherry, Cottonwood, Elm, Hickory, Hornbeam, Larch, Maple, Sassafras.

Chemical Control: Sevin, Eight, or Methoxychlor Non-Chemical: Thuricide, or Dipel are Bacillus Thuringiensis products. Montereys' Garden Insect Spray

Applications should be done in the early evening, as insects are active at night. Wrapping trees in burlap or sticky foil will help prevent insects from climbing to the tops of trees. Burlap must be removed during the day so that larva can be collected and killed. The control for adult moths is a trap for males that can prevent mating and subsequent generations.

TENT CATERPILLARS

The eastern tent caterpillar is the most prominent in this area. Larvae are black, with white stripes down their backs and yellow lines with blue dots down their sides. They hatch out and reach maturity at 2" in about six weeks. The caterpillars spin silky webs in the forks of trees in April to May. They enlarge the tent as they grow, sometimes covering entire branches.
Hosts
Apple, Birch, Black Gum, Cherry, Crabapple, Hawthorn, Peach, Plum, Wild Cherry

Chemical Control: Sevin, Eight, or Methoxychlor Non-Chemical: Thuricide, Dipel. Montereys Garden Insect Spray

Early morning applications are the most effective as tent caterpillars feed during the day and return to the tent at night. Break open the tent if possible prior to spraying. You can also remove and destroy the tents at night. Control is only effective while caterpillars are still growing. Once mature, they stop eating and spin a cocoon.

ALWAYS READ AND FOLLOW LABEL DIRECTIONS WHEN USING PESTICIDES.