Bagworms

How to spot it

• Spindle-shaped bags hanging from branches, up to about 2 inches long
• Bags covered with bits of leaves and twigs laid like shingles
• Thinning, chewed, or browning foliage on junipers, cedars, and arborvitae
• Tiny caterpillars in small bags in late spring
• Full-grown caterpillars up to about 1 inch long inside the bags

Why it shows up

Eggs spend the winter sealed inside the bags. They hatch in late spring, and the caterpillars feed and grow all summer. They pupate in August or September. There is one generation a year. Bagworms feed on many evergreens and broadleaf trees and shrubs.

How we treat it

We will identify it on a visit and recommend the right fix. Picking bags off by hand in winter is the cheapest control. Late spring, while the caterpillars are small, is the best time to act. If it is heavy, we will talk through your options with you.

What you can do

• Pick bags off by hand in winter and throw them away. Do not leave them on the ground.
• Check junipers and arborvitae in late spring for tiny bags.
• Call early if foliage is thinning. Bagworms can kill juniper and arborvitae.