Bagworm Moths on the Fruit Trees: Identify Garden Pests

Bagworm moths on fruit trees can cause a lot of damage. Here’s how you can identify these destructive insects.

Bagworm Moths on Fruit Trees – Common Pest

This is my first experience with the bagworm moth. My husband first noticed these things hanging from our apricot trees in the fruit tree orchard last fall when he was cutting the lawn. It was after the leaves had fallen, and he simply assumed it was two leaves that just hadn’t fallen off of the trees yet.  He took a closer look and pointed them out to me, suggesting they were some sort of moth or butterfly cocoon.

Bagworm moths on fruit trees use pine needles to camouflage its cocoon and we thought that was interesting. We found another one on the wire cages we use around the apple trees to keep the deer away from the young trees.

Another bagworm. They’re clever with that camouflage.

About two weeks ago, my friend and gardening mentor Liz gave me a copy of Virginia Gardening magazine. Another friend who is a garden writer and photographer and in the Master Gardening program too, Cynthia Wood, published a lovely article on Liz’s water gardens in that March issue, and Liz lent me her copy so I could show my husband her beautiful gardens.  John was reading the magazine and called me over to look at an article I hadn’t noticed.

It was a two page spread featuring insects and there was something that looked like our cocoon.  It was identified as a ‘bagworm’ but the article didn’t give us any information on it. Was it bad? Did it eat the fruit or the tree? Or was it a benign presence in the garden?

I took the photos you see here and emailed them to Liz. I printed them out too and brought them to my Master Gardener class on Wednesday night.  Sure enough, everyone positively identified it as a dreadful pest called the ‘bagworm moth.’

Life Cycle of the Bagworm Moth

The female larvae find a host tree and create the thick bag you see in the picture using twigs, leaves and evergreen needles as camouflage. In the spring, the male moths fly to the females for mating, and the offspring larva emerge from the bag-like structure. The female spins a larger, silky bag to protect her offspring.  They emerge in June, according to the Virginia Cooperative Extension website, and begin eating the leaves from the trees. Females remain on the tree or have to crawl to a new host while the males fly off eventually to start the cycle all over again.

Infestations Can Kill Entire Trees

Liz tells me that an infestation of bagworm moths killed a large row of juniper trees in our town of Farmville, and that they can be quite bad.  John and I used gardening pruners and removed the bags and threads from the trees and from the wire cage. I sealed them into an empty cottage cheese container that we had in the recycle.  We will kill them later today.  I dislike killing anything, but honestly, I can’t catch and release something that can potentially damage our garden or a neighbor’s farm. It just isn’t right.

Vigilance Helps Prevent Problems

I’m grateful for several things. First, that both my husband and I are vigilant. We are observers and love to note and discuss what we see on our walks, or while gardening.  We’re always calling attention to unusual insects, wildflowers, animal prints and such.   We’re both curious by nature and enjoy researching things too, so researching insects and such is in our nature.

I’m grateful for the Master Gardeners (thank you Liz and the team at class!) and for the Cooperative Extension to help identify such pests. Most of all, I am grateful we were able to remove what we could see NOW in March and not have to deal with an infestation in June.  I can only imagine the potential damage, and we have invested three years of TLC into those apricot trees!

Here are links to more information on the bagworm moth:

• Virginia Cooperative Extension
• Penn State Cooperative Extension