2 Sure Cures for the Bagworm Blues

No, it's not a rustic Christmas tree ornament--it's a bagworm nest! And it can kill your conifers if left unchecked.
No, it's not a rustic Christmas tree ornament--it's a bagworm nest! And it can kill your conifers if left unchecked. | Source

Got the bagworm blues?

If you live in the eastern U.S., you've probably seen your share of bagworms (Thyridopteryx ephemeraeformis) . It's not uncommon for large infestations to plague forestland along neglected roadways or, if you're unlucky, within your own landscape.

Bagworms spin cobweb-like "bags" in trees and shrubs. They particularly like to infest conifers such as pine, cedar, arborvitae, Leyland cypress and juniper. Sometimes, they're so prolific that they kill their host tree. Because the bags are shaped like pine cones, they often pass unnoticed in conifers--until it's too late.

Bagworms may also spin cocoon-like nests in deciduous trees, such as locust, maple, linden, sycamore and boxelder. Although these trees may suffer damage, unlike conifers they're rarely killed by bagworms. Nevertheless, few homeowners want even one bagworm nest in their yard.

Where do bagworms come from?

Bagworms are actually moths in their larval (caterpillar) stage of development. After hatching, moth caterpillars spin cocoon-like bags. These bags have pieces of leaves from the plants they're feeding upon attached to them.

At first, the bags are very small--only about 1/8 inch long. The young bagworms move about freely as they feed, carrying their bags with them, enlarging it as they themselves grow bigger.

It's at this point--when moth caterpillars are young--that they're easiest to destroy through the application of a bacteria commonly called BT.

Insecticide Organic Dipel DF 16 Ounce Bag (vob)
Insecticide Organic Dipel DF 16 Ounce Bag (vob)

When applying Dipel (or any BT spray) be sure to wear protective clothing.

 
Southern AG Thuricide HPC Concentrate, 8 oz
Southern AG Thuricide HPC Concentrate, 8 oz

Products containing BT are most effective on young moth caterpillars.

 
3M Paint Project Respirator, Medium
3M Paint Project Respirator, Medium

When applying sprays, be sure to wear protective gear.

 

How to Get Rid of Bagworms

Bagworm-killing bacteria

Bacillus thuringiensis (BT) is a bacteria that kills certain insects, including bagworms, but it doesn't adversely affect humans or other animals.

BT works extremely well against young moth caterpillars, so if you're going to use BT, be sure to apply it early.

Common brand names of products that contain BT include Dipel, Caterpillar Killer and Thuricide.

Pesticides

These insecticides are also labelled for bagworm management: Bifenthrin Pro Multi-Insecticide, Onyx Insecticide, Talstar F, Talstar Lawn & Tree Flowable, Talstar GC Flowable, TalstarOne Multi-Insecticide and Dursban 50W.

Like BT, they should be applied shortly after the moth eggs hatch.

Handpicking

Removing bagworm bags from trees by hand isn't as gross as it sounds. Remove the bags in winter or early spring (before the moth eggs hatch) and destroy them.

How NOT to Get Rid of Bagworms

You may have heard of gardeners pouring gasoline on bagworm bags and then setting them on fire. It's a dangerous practice that could cause serious damage to you, your tree and/or your property. Don't try it! Stick with handpicking the bags when the eggs are dormant. Or, if your infestation is severe, opt for BT or some other non-petroleum chemical solution. Those are the best ways to beat the bagworm blues.

More by this Author


Comments 11 comments

The Dirt Farmer profile image

The Dirt Farmer 3 years ago from United States Author

Thanks so much, Stellar Phoenix! A good review is an awesome thing. (: Take, Jill


Stellar Phoenix 3 years ago

This content is incredible! You certainly know how to keep a reader entertained. Between your wit and your videos, I was almost moved to start my own blog (well, almost..aha) Fantastic job. I really loved what you had to say, and more than that, how you presented it. Too cool! Stellar Phoenix Review


The Dirt Farmer profile image

The Dirt Farmer 4 years ago from United States Author

@ lrc7815 -- How horrible. Bagworms can really cause some serious damage. Hope the info helps you keep the rest of your trees safe. Take care, Jill


The Dirt Farmer profile image

The Dirt Farmer 4 years ago from United States Author

@ lrc7815 -- How horrible. Bagworms can really cause some serious damage. Hope the info helps you keep the rest of your trees safe. Take care, Jill


lrc7815 profile image

lrc7815 4 years ago from Central Virginia

Great hub. Wish I had had this information a few y ears ago when I lost two 30 year old junipers to bag worms. Thanks for sharing this great information.


tebo profile image

tebo 5 years ago from New Zealand

I have never heard of bagworms and am unsure whether we have them here in NZ, but I do have some conifers so I will check them. Thanks for the heads up.


NMLady profile image

NMLady 5 years ago from New Mexico & Arizona

Re bag worms don't vacation in NM....Yep, I am very glad!


The Dirt Farmer profile image

The Dirt Farmer 5 years ago from United States Author

No, I haven't tried it--although I know someone who uses it in his fruit orchard. Thanks for your comment! Aren't you glad bagworms don't vacation in NM?


NMLady profile image

NMLady 5 years ago from New Mexico & Arizona

Have you ever tried diatomaceous earth? (ground up coral) It is a pretty good bug killer w/o being poisonous to warm-blooded animals like us and our pets.

I DO remember these and they are yucky.


The Dirt Farmer profile image

The Dirt Farmer 5 years ago from United States Author

Thanks, Esmeowl12. Hope you have time to pick off the dormant bags once the weather gets colder. Although bagworms spread slowly, they do spread! Happy gardening, DF


Esmeowl12 profile image

Esmeowl12 5 years ago from Sevierville, TN

Wow. I never knew that's what these are. I have a few, thankfully not many. I appreciate the info. Voted up and useful.

    Sign in or sign up and post using a HubPages Network account.

    0 of 8192 characters used
    Post Comment

    No HTML is allowed in comments, but URLs will be hyperlinked. Comments are not for promoting your articles or other sites.


    Click to Rate This Article
    working