How To Get Rid of Bagworms: Treatment To Save Trees From Bag Worms Nest

Georgette Kilgore headshot, wearing 8 Billion Trees shirt with forest in the background.Written by Georgette Kilgore

Pest Control | March 28, 2024

Woman holding a bagworm wonders how to get rid of bagworms and if there is a bag worm treatment guide that explains how to remove bagworms, how to identify bag worms, nest, cocoon, and when to spray for bagworms.

When gardening it can be important to know how to get rid of bagworms and just as important to know how to recognize them to safeguard the health of your plants.

Bag worms are a common pest that can pose a threat to many different kinds of trees and plants in your backyard, and if you don’t know what they look like they will devour all the leaves from your plants quickly.

To stop that from happening, knowing what to look for in early infestation signs can help.

This complete guide explains how to spot bagworms before the become a problem, as well as how to get rid of bagworms and kill bag worm nests effectively.

Bag Worm Treatment: How To Get Rid of Bagworms

Perhaps the most straightforward way to get rid of bagworms without having to worry immediately about exterminator prices is to hand-pick them off the tree.

A sharp tug will break the thin silk strands and the cocoons can then be discarded.

Graphics with illustrations and text showing how to get rid of bagworms on trees.

This quick, simple, and effective method of bag worm treatment works well and you won’t have to worry about an angry bagworm nipping at your fingers as they don’t bite people.

The only drawback is that it will take a lot of time to differentiate the tiny cocoons from normal parts of the tree and then ensure that you get every single last one.

It doesn’t matter whether you start picking them from the tree as early as possible at the start of the season in May, but for other forms of pest control earlier is preferable to later.

This is because the key how to get rid of bagworms is both simpler and more successful if treatment begins early in the season rather than when they mature and become harder to kill.

Pyrethroid insecticides are the most effective for late-season applications but the early in the life cycle of the bagworm the better with insecticides that are formulated specifically to eradicate this invasive pest.2

What about vinegar? Will vinegar kill bagworms or another form of homemade organic compound?

A woman spraying chemicals on plants.

(Image: Sasha Kim10)

Organic alternatives might be useful if you are averse to using harmful chemicals on your trees and bushes that may contribute to the amount of greenhouse gas emissions emitted worldwide.

However, these alternatives do not necessarily provide the same results as chemicals, as appealing as the notion of utilizing dishwashing solutions seems. For them to be effective, you have to physically puncture the bags before spraying your homemade spray for bagworms onto the caterpillars inside.

If this is the option you wish to take, remember that at the start of the season will be the best time when to spray for bagworms.

Treatment To Save Trees From Bag Worms Nest

Another organic and natural product that can be used to eliminate bagworms, is neem oil. Just as with applying dish soap mixed with water, the cocoons have to be pierced, and repeated applications may be necessary to eliminate them completely.

There are different levels of strength in the insecticides available but regardless of which one you use, be sure to follow the directions on the packaging which will direct you to don protective gear to prevent inhalation or exposure to your skin. Any gardening center will have a range of products with varying speeds at which they take effect, and levels of potency.

Some will have all-natural organic ingredients that may be more to your liking, and the store can advise you on which product is more appropriate for your particular circumstances. After treating your trees with the product, you may want to take extra precautions to prevent a resurgence of the bagworm infestation by routinely inspecting your property’s bushes and trees.

How To Kill Bagworms Naturally

Interestingly, there is a way how get rid of bagworms without laying a finger on them.

Although they don’t look very appetizing wrapped in a cocoon made of bits of twigs and leaves, to certain birds they are a tasty morsel and an irresistible treat. If you want to rid your plants of them, install bird baths, hang bird baskets sprinkled with seeds, or plant flowers that these birds are attracted to, to lure small but predatory birds into your yard.

And the same goes for Trichogramma wasps. You can actually purchase these parasitoid wasps at some garden centers if you have a particularly nasty infestation and are reluctant to use any form of chemicals, and they are very simple to employ.4

When you get home, all you have to do is set them free on the infected tree and they will find where the bagworms are hanging out but, unlike the birds who devour them hungrily and on sight, the wasps will simply lay their eggs in the actual eggs of the bagworms.

As soon as the bagworm larva hatch, they are served up like a ready meal to the larva of the wasps who dine on them at their leisure.

If you’re a touch too late and the moths have already taken flight and avoided the wasps, a third option is to plant plants. There is a large range of flora that naturally repel moths and keep them at bay.

If you plant marigolds, chrysanthemums, thyme, lemongrass, and rosemary then you won’t have the moths invading your space looking to mate in the first place.

When To Call Exterminators for Bagworms

Bagworms have the capacity to overwhelm a landscape. Imagine a thousand females bearing a thousand eggs each that all hatch at the same time.

Even if you become aware early enough of their presence there’s not much you can do to get rid of them all before your evergreen trees, shrubs, and plants are rendered leafless.

A woman spraying insecticide on young trees.

(Image: Gustavo Fring11)

Here’s when to call exterminator for bagworms. It’s time to call in the professionals. When deciding which one to choose, verify what certifications they hold such as the International Society of Arboriculture (ISA), how long they have been in the industry, and ask to see any references.

A qualified and experienced exterminator will have all three on hand and be able to explain the range of available treatments. Arborists understand the life cycle of bagworms and know how to get rid of bagworms no matter their population size. They will have chemical solutions, fertilizers, organic sprays, solutions with beneficial nematodes, and a whole host of methods that are fast-acting or slow-releasing.7

They may provide a follow-up service in situations where hundreds or thousands of bagworms may be at different stages of development and require tailored solutions.

Word-of-mouth is undoubtedly one of the best methods of verifying the qualifications of an arborist, and finding the most capable to rid yourself of a tree full of invasive bagworms.


(Thyridopteryx ephemeraeformis Haworth)

Image of a bagworm in an oval frame on green background.
  • Description: A caterpillar that spends its entire life cycle wrapped in a cocoon that is ¼ up to 2 inches long
  • Natural Habitat: Native to North America
  • Locations: Bagworms are comfortable in willow, juniper, oak, maple, pine, and spruce trees.

Image Credit: sandid12

Bagworm Cocoon

Their name comes from the cocoons newly hatched moth larvas start to make as soon as they enter the world. They construct them out of a combination of leaves, twigs, and the silk thread that they skillfully weave to hold all the components together.

Each cocoon is fashioned in such a manner that it melds into the foliage of the tree or plant, camouflaging itself from predators and even gardeners wary of their presence in the area.

Once the cocoon is completed it becomes their home and is attached to the branches or twigs by a thin yet strong strand of silk, hanging like an appendage with the caterpillar snugly inside its small home, a home that grows when it grows and moves when it moves.

Their movements are not easy to spot as being one with the tree is part of their survival mechanism, but almost imperceptibly they feed by relocating their tiny home along the branch in slow motion until they get to the next bunch of leaves where they intend to feed.

One bagworm is nothing for a healthy plant to fear.5 Hundreds of bagworms are another matter as together they can strip every green leaf from your favorite plant in slo-mo.

Close up photo of a bagworm cocoon hanging on a small branch.

(Image: koshinuke_mcfly8)

And then, once they’ve done their worst, they transport themselves to the next plant by an interesting method called ballooning. Cleverly spinning a web around the cocoon, they wait until there is a consistent breeze and then just drift towards the next plant.

Bagworms Nest

The cocoon is not just a temporary home but is actually a breeding nest where the females literally spend the rest of their caterpillar lives inside, enlarging the nest as they grow and preparing it for the next generation.

The males remain inside until they become moths in about 4 to 5 months and then fly free to seek out females to mate with. The wingless females are left behind in a spacious cocoon that is now about 2 inches long whereas before it was a mere ⅛ of an inch in length.

Now permanently secured in just one location, the female lays anywhere between 200 to 1,000 eggs and once the last egg is produced, she promptly dies.

If left undisturbed, the eggs will spend the winter safely cocooned in the nest until the following spring; unless they are eaten by birds and other bugs.

Photo of bag worms nest hanging by a branch.

(Image: Guayo9)

But even then they are protected. Even as they are consumed by birds they are protected by thick shells that keep them completely safe from harm and the armored eggs just travel through the bird’s digestive system unaffected, and strangely enough this attempt at being devoured by another species serves in the dispersal of the bagworm species.

Are Bagworms Harmful?

It is deceptively easy for hundreds of bagworm cocoons to position themselves within a tree or bush that has very thick foliage without being noticed.

The caterpillars make their cocoons out of the very materials that the plant is composed of and are sometimes indistinguishable from their host, especially when they are first formed and are so tiny.1

The cocoons become bigger as the caterpillar grows and they are only going to get bigger as they keep eating more of your plant’s foliage. That level of defoliation will increase slowly at the start, with just one or two branches that may be attributed to lack of water, but the rate will quickly increase as the bagworms grow and the numbers become overly excessive.

In many cases, the damage caused by bagworms is not seen by the untrained eye until August at which point they have probably been hanging around and merrily munching away for months. They can and will cause long-lasting harm to your evergreen trees, heavily affect shrubs, and many other types of plant species may simply be nibbled away to nothing and die or have to be destroyed.

So, after noticing their characteristic cocoons, how to get rid of bagworms before losing your tree has to be at the forefront of your mind.

The Plaster Bagworm

The plaster bagworm prefers the inside of your home compared to their tree-hanging counterparts who like the great outdoors. Similarly, they construct their cocoons from readily available household substances like lint, fibers, human and pet hair, and anything else they can scrape together to make their nest nice and cozy.

The life cycle differs slightly where the male, who is still the only one with wings and able to leave the nest, dies along with the female after mating. A tragic end to a brief love story, the results of which will be 200 pale blue eggs.

One or two of the cocoons may not be noticeable or even noteworthy, but in about 2 to 3 months when more start popping up in more corners of your home they may register on your peripheral radar. Apart from looking unsightly, are they harmful?

Not at all. They won’t pester you or your pets, they won’t even chew on your plants, but your socks, your jumpers, your towels, your curtains, even your carpets, and every other piece of clothing that you have is fair game.

To get rid of them real quick, get out your vacuum cleaner with a long extension on it or pluck them off the wall by hand and dunk them in a bowl or bucket of soapy water to finish them off. Reducing the temperature by the use of air conditioning may help to scare them off as they prefer humid homes, but it’s not always effective.

If the problem is severe enough and your clothes have more holes than their original design, you may always resort to the tried-and-true approach of applying an organic solution for indoor usage. In extreme circumstances, it may be necessary to call in a pest control service for assistance.3

How To Get Rid of Bagworms: Pest Control for Bagworms

Plaster bagworms may rapidly spread because of their high reproductive rate, the fact that mature males can fly, and their unusual trick of ballooning from plant to plant.

The skill to controlling them is timing, applying treatment as early as possible during their pupation stage when they are about to start eating every leaf they can shuffle up to.

As the females become older and prepare to lay eggs, they tend to eat less, secure themselves in one place inside their cocoons, and are less susceptible to pesticides, organic or otherwise.

However, to help fight climate change and reduce carbon dioxide emissions, finding an organic and eco-friendly method for how to get rid of bagworms will do wonders for your plants and reduce your carbon footprint.

Frequently Asked Questions About How To Get Rid of Bagworms

Do Bagworms Attack Only One Type of Tree?

Yes and no. Bagworms may be either monophagous and only eat one kind of plant, or polyphagous and eat the leaves of several kinds of plants, and even some species of tiny insects.


1Missouri Department of Conservation. (2023). Defoliating Caterpillars. Missouri Department of Conservation. Retrieved December 6, 2023, from <>

2Pennsylvania State University. (2023, March 9). Fungicides, Herbicides, and Insecticides. PennState Extension. Retrieved December 6, 2023, from <>

3United States Environmental Protection Agency. (2023, June 29). Tips for Selecting a Pest Control Service. EPA. Retrieved December 6, 2023, from <>

4University of California Agriculture and Natural Resources. (2023). Trichogramma Parasitoids. UC IPM. Retrieved December 6, 2023, from <>

5University of Florida. (2013, February). common name: bagworm scientific name:Thyridopteryx ephemeraeformis Haworth (Insecta: Lepidoptera: Psychidae). Featured Creatures. Retrieved December 6, 2023, from <>

6University of Maryland, Baltimore County. (2020, December 15). Virgin births from parthenogenesis: How females from some species can reproduce without males. UMBC. Retrieved December 6, 2023, from <>

7University of Massachusetts Amherst. (2021, December). Biological Control: Using Beneficial Nematodes. The University of Massachusetts Amherst. Retrieved December 6, 2023, from <>

8Bagworm Photo by koshinuke_mcfly / マクフライ 腰抜け. Resized and Changed Format. Pixabay. Retrieved January 4, 2024 from <>

9Bagworm Nest Photo by Guayo. Public Domain. Resized and Changed Format. Wikimedia Commons. Retrieved January 4, 2024 from <>

10plant spray Photo by Sasha Kim. Resized and Changed Format. Pexels. Retrieved January 4, 2024 from <>

11Person Spraying a Tree Photo by Gustavo Fring. Resized and Changed Format. Pexels. Retrieved January 4, 2024 from <>

12Bagworme Caterpillar Leaf Case Moth Photo by sandid. (2016, March 4) / Pixabay Content License. Cropped and added text, shape, and background elements. Pixabay. Retrieved February 16, 2024, from <>