Find out how to get rid of bagworms before they destroy your evergreens and other plants.
Here’s how to recognize and get rid of bagworms on your plants.
Laura Iles, Ph.D., is the director of Iowa State University’s North Central Integrated Pest Management Center.
Credit:Courtesy of Getty Images / Backyard Production
What do bagworms look like?
Bagworms are easy to miss at first.
Conical at first, diamond shaped later, theyre interwoven for strength and naturally colored for camouflage.
Bagworm Life Cycle
Bagworms feed from the time they hatch in late spring/early summer until late summer.
At that point, they seal their bags and transform into moths in preparation for mating.
The adult female remains in her bag while a winged male moth visits to mate.
This is why infestations build up over time, Iles adds.
Serious attacks may call for other measures.
Do not leave them in the garden, as larvae may return to the host plant.
Chemical Treatment
A pesticide spray may be more practical than hand-picking for very large infestations.
This is typically from early to mid-June.
The caterpillar needs to consume the product to get to be killed.
Younger caterpillars are more easily killed and this prevents more damage.
Treating large caterpillars later in the season is not effective.
A follow-up treatment may be necessary if damage continues.
Multiple applications may be needed.
These natural formulations have less impact onbeneficial insectsthat attack bagworms.
Organic options such as Bt are very effective.
Cultural Treatment
Parasitic wasps and tachinid flies feed on bagworm larvae.
you’ve got the option to encourage their presence by avoiding chemical sprays.
Alsoconsider planting astersand daisies, which are especially good for attracting these beneficial insects when planted near vulnerable plants.
When to Call an Arborist
The best option may be to enlist the services of acertified arborist.
Arborists have the equipment needed to adequately treat larger trees.
It also saves the homeowner from having to store leftover chemicals.
