These are the common tent forming caterpillars that show up early in the spring. They are different from the fall webworms which, as the name implies, make their nests late in the summer into the autumn.

Eastern tent caterpillars form their nests in the crotch of tree branches. They are perhaps most common on crabapple trees although they may be found on other species too such as hawthorn, maple, cherry, peach, pear and plum.

The adult lays eggs on the bark of the tree in the fall. In the spring as the leaves are opening from the buds, the eggs hatch and the caterpillars do too. As they feed, the spin a web nest that expands as the season progresses. In about mid-summer, the 2 to 2 1/2 inch long caterpillars form cocoons and in about 3 weeks a small, brownish moth emerges.

Generally speaking, these critters are more of an aesthetic problem in the home landscape. Sure they eat some leaves but, unless there are many nests in a small tree, not enough to seriously hurt the tree. The large, silky nests, however, are an eyesore on a nice crabapple in the yard.

There are a couple of approaches to prevent Eastern tent caterpillars from making a mess in your trees:

1. Remove Egg Masses - As mentioned above, the adults lay their eggs on the bark of trees in the fall. If you look closely near the crotch of susceptible species of trees, you may be able to see the egg masses. Scrape them off (without damaging the bark, of course) into a pail of soapy water.

2. Catch Them Early - The eggs will hatch at the same time as the leaves appear on the tree. Nature has worked it out so that the hungry little creatures stir into life just in time to have a meal. So, when you see the leaves, take a close look in the crotches between main branches and the trunk of the tree. Within a week or two of leaf emergence, you should begin to see tiny webbed nests starting to be formed. At night or in the heat of mid-day, carefully remove the nest and put it in a pail of soapy water. The caterpillars tend to be out eating in early morning and evening and are usually in the nest during the heat of the day or on rainy days.

There is only one generation per year so, if you do this once, it should take care of the problem until the following spring.

If you did not catch the problem (see Problem Prevention above), you can still control damage from the Eastern tent caterpillar. In fact, this is the situation for most people who don't notice them until the nest is quite large and the caterpillars are already near the end of their 4 to 6 week feeding cycle.

First and foremost, DO NOT BURN THE NEST!!! Sure that will get rid of the caterpillars and may make you feel better...however, it will also do far more damage to the tree than the caterpillars.

Again, you can tear down the nest at the times when the caterpillars are inside or you can treat the nest and tree with an insecticide that is labeled for Eastern tent caterpillar.

Note: We have provided some general information and observations on this topic aimed at the home gardener. Before you take any serious action in your landscape, check with your state's land grant university's Cooperative Extension Service for the most current, appropriate, localized recommendations.

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