Filed under: Pests, trees | Tags: bag worm, defoliator, eastern tent caterpillar, pyrethrin, trees
“They’re baaaaack.” Have you noticed the bag worms yet? Likely, most people never notice the bag worms themselves, but the bags are hard to miss. Eastern tent caterpillars, commonly known as bag worms, have already hatched from their eggs. The larvae (caterpillars) spin their silk into a web nest (or “bag” or “tent) in the branches of trees. As you might have noticed, these nests house hundreds of larvae, protecting them from predators. The larvae are not restricted to the nest, however. They spend much of their time eating the tree’s leaves, only returning to the safety of the nest when not feeding. During their early development, the larvae feed during the day and return to the nest at night. Later in their development, the larvae reverse this, feeding at night and retreating to the nest during the day.
Are these bag worms a problem? They can be. They voraciously feed on leaves and can defoliate large sections of tree quickly. The bag nests are also an eyesore.
If you want to treat these pests, it will be easiest and most efficient when done early in the season (now!). Also, treatment is best done at dusk, when you will have the best chance of finding the larvae in the nest. Here are two options:
- If you have few nests that are accessible, and you aren’t squeamish, you can manually remove the nest (we suggest using a stick or the handle of a tool) and handpick the larvae, placing them in soapy water.
- Use a pyrethrin spray, a botanically-derived insecticide (safe for use near people and pets). Break open the nest with a stick, then spray with pyrethrin. The spray works very quickly on the larvae.
Good luck!
Leave a Comment so far
Leave a comment
