If you live in southwest Virginia, chances are you’ve seen your fair-share of bagworms. These pesky, destructive insects can be seen enveloping the branches of deciduous and evergreen trees in the spring and summer. Bagworms encase themselves in a silk “bag” and feed on needles and leaves, sometimes completely destroying a tree’s foliage. As their bags grow bigger, they also grow harder and harder to penetrate and destroy, and, once bagworms start breeding, they can become difficult to control. This is bad news for gardens and yards but, luckily, there are various ways to remove bagworm populations before they become a big problem. Here are a few you might consider:
Bagworm caterpillars typically hatch towards the end of May or early June. Keep an eye out for these bugs early on, regularly inspecting leaves and needles for their presence. Soon after hatching, they are very susceptible to insecticides with bifentherin in them. When searching for the right insecticide, be sure to get one that controls for lepidopteran insects (ie. bag worms) and spray on affected areas. This will nip the problem in the bud before it gets out of hand.
Spraying tip: When applying insecticide, be very thorough in your application. Spray from branch tip to trunk and apply to both inside and outside foliage.
Looking for an organic spray treatment option? Try anything labeled with Bacillus thuringiensis or neem oil.
If you would rather forego a chemical treatment, physically removing the bagworms after their peak season can also help control their population. They breed in early Fall and store their eggs in the bags over the winter. In late fall, you can begin removing the egg-filled bags by hand before the babies have an opportunity to hatch. This will cut down on bagworm populations the following spring. Just be sure to be very thorough in your removal to avoid leaving eggs behind.
If the problem becomes severe, always contact a professional! A nasty bagworm infestation might require numerous applications of insecticide that are best left to the pros.