Bagworms, also known as Thyridopteryx ephemeraeformis, are a common pest that can wreak havoc on your garden and landscape.
These destructive creatures feed on a variety of ornamental plants, spinning cone-shaped bags from silk and embedding them with debris from their host plants as they grow.
Noticing the telltale bags on your trees and shrubs is an indicator that it’s time to take action.
Fortunately, there are natural methods to control and eliminate bagworms in your garden without resorting to harsh chemicals.
In the following article, we will explore various eco-friendly options for dealing with these pests, ensuring that your plants remain healthy and vibrant throughout the growing season.
So, let’s dive right in and learn how to get rid of bagworms naturally, protecting our beloved gardens from harm.
Understanding Bagworms
Life Cycle
Bagworms, or Thyridopteryx ephemeraeformis, are the larval stage of a moth species. Their life cycle begins when eggs hatch around May in central regions1.
The newly hatched larvae immediately create small, 1/8-inch cocoon-like bags from silk and plant materials for protection2. As they grow, their bags expand, eventually reaching 1½ to 2½ inches long3.
Adult bagworms emerge in late summer, with males developing into brown, fuzzy moths capable of flying4.
Females, however, remain wingless and stay inside their bags to lay eggs5. The next generation hatches the following spring to continue the cycle6.
Signs of Infestation
Infestations become evident when many cone-shaped bags on your trees’ branches7.
These can often appear brown and blend in with the surrounding foliage, making them difficult to spot8.
Additionally, affected trees may exhibit defoliation or dying branches, and evergreen trees may show brown, damaged needles9.
Commonly Affected Trees and Shrubs
Bagworms have a wide range of host plants, making them common landscape pests. The types of trees and shrubs they tend to infest include:
While bagworms mainly target evergreen species, they can harm deciduous trees as well19.
Monitoring and early treatment play a crucial role in preventing severe damage to your plants.
How to Get Rid of Bagworms Naturally
Birds as Predators
Attracting birds like sparrows, titmice, chickadees, and nuthatches can help control bagworm populations.
These birds are natural predators of bagworms, feeding on them in their larval stage. You can attract these birds by providing birdhouses, feeders, and water sources.
Handpicking and Removal
Handpicking and removing bagworms is an effective way to control their population.
This method works best during the fall, winter, and spring when bagworms are less active. Simply pick off the bags from infested trees1.
Remember to:
- Destroy the picked bags
- Dispose of them in the trash
Introducing Natural Predators
Introducing natural predators, like Trichogramma wasps and ichneumonid wasps, can help manage bagworm populations.
These wasps target bagworm eggs and larvae, keeping the infestation under control.
Pros:
- Natural and chemical-free
- Aids in maintaining ecological balance
Cons:
- May not work as fast as chemical treatments
Moth-Repelling Plants
Planting moth-repelling plants, such as lavender and marigold, can help deter adult bagworm moths from laying eggs on your trees and plants.
These plants emit a scent that moths find unappealing, keeping them away from your foliage.
Managing Outdoor Lights
Reducing or managing outdoor lighting can help control bagworm populations.
Bagworm moths are attracted to lights at night, so lowering the brightness or using specialized bulbs can discourage them from laying eggs near light sources.
- Use dimmer lights in outdoor spaces
- Opt for yellow, sodium vapor lights instead of white lights
Using Natural Insecticides
Bacillus Thuringiensis
Bacillus thuringiensis (Bt) is a naturally occurring bacteria that acts as an effective insecticide against bagworms.
When ingested, Bt releases a toxin that destroys the digestive system of the bagworm larvae1. Some pros and cons of using Bt include:
Pros:
- Safe for humans, pets, and beneficial insects
- Biodegradable and environmentally friendly
Cons:
- Requires proper timing (must be used during larval stage)
- Can be washed away by rain
Neem Oil
Neem oil is another effective natural option that helps control bagworm infestations2.
Extracted from the seeds of the neem tree, it works by disrupting the insect’s feeding and growth habits. Some advantages and disadvantages of using neem oil include:
Pros:
- Acts as an insecticide and repellent
- Safe for beneficial insects
Cons:
- May require multiple applications
- Can cause injury to some plant species
Soapy Water Solution
A simple solution of water and dish soap can help remove bagworms from infested plants manually3.
The soapy water suffocates the bagworms and makes picking them off easier. However, care should be taken to avoid damaging the plant with excessive soap4.
Pros:
- Cost-effective and readily available
- Easy to apply
Cons:
- May damage plants if not properly diluted
- Requires manual removal of bagworms
Comparing the three natural insecticides:
| Insecticide | Effectiveness | Safety | Ease of Application | Additional Benefits |
|---|---|---|---|---|
| Bacillus Thuringiensis | High | High | Moderate | Environmentally friendly |
| Neem Oil | Moderate | High | Moderate | Repellent |
| Soapy Water Solution | Moderate | High | Easy | Cost-effective |
Additional Tips and Considerations
Timing and Application
It’s crucial to act at the right moment for effective bagworm control. In general, you should start managing bagworms during their larval stage in early spring.
Applying treatments while caterpillars are young will yield better results.
Handpicking is a viable option during winter, while the use of neem oil or chemical-based insecticides is advised for early spring applications.
Dealing with Large Infestations
For significant infestations, consider using more aggressive methods, such as chemical-based insecticides. However, we will not suggest using them unless the situation is drastic.
Pros:
- Effective in exterminating bagworms
- Works well for large-scale infestations
Cons:
- Can be harmful to beneficial insects
- Potentially dangerous for pets if not used carefully
Some of the commonly used chemical insecticides include malathion, diazinon, and carbaryl.
Safeguarding Pets
To keep your pets safe while dealing with bagworm infestations, follow these guidelines:
- Keep pets away from treated areas until the chemicals have dried.
- Choose pet-friendly insecticides, like neem oil.
- Use natural predators, such as woodpeckers, to control bagworm populations.
Remember that preventing bagworm infestations is more manageable than treating them.
Regularly inspect your plants for signs of bagworms, and remove any cocoons or debris to deter their growth.
Comparison Table: Neem Oil vs. Chemical Insecticides
| Neem Oil | Chemical Insecticides | |
|---|---|---|
| Effect | Natural and less potent | Fast-acting, more potent |
| Safety | Pet-friendly and eco-safe | Requires caution with pets |
| Coverage | Better for small infestations | Suitable for large infestations |
| Cost | Generally cheaper | Can be more expensive |
Conclusion
To summarize, Bagworms can be controlled by using various natural methods, such as hand-picking, pruning, spraying with water or soap, introducing beneficial insects or bacteria, or applying organic products like neem oil or diatomaceous earth.
These methods are effective, safe, and eco-friendly. Application of these natural repellants and insecticides varies with agent, as is described in the article above.
Footnotes
- https://extension.umd.edu/resource/bagworms-trees-and-shrubs ↩ ↩2 ↩3
- https://ohioline.osu.edu/factsheet/HYG-2149-10 ↩ ↩2
- Ibid. ↩ ↩2
- https://extension.unl.edu/statewide/douglas-sarpy/pdfs/ce/resources/ce-how-to-control-bagworms.pdf ↩ ↩2
- Ibid. ↩
- Ibid. ↩
- https://content.ces.ncsu.edu/bagworms ↩
- https://ohioline.osu.edu/factsheet/HYG-2149-10 ↩
- https://extension.entm.purdue.edu/publications/E-27/E-27.html ↩
- https://content.ces.ncsu.edu/bagworms ↩
- Ibid. ↩
- Ibid. ↩
- Ibid. ↩
- Ibid. ↩
- Ibid. ↩
- Ibid. ↩
- Ibid. ↩
- Ibid. ↩
- https://extension.umd.edu/resource/bagworms-trees-and-shrubs ↩
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about bagworms. Scroll down to have a look at some of them.
Letter 1 – Bagworm
Subject: Chrysalis
Geographic location of the bug: South Florida (Punta Gorda)
Date: 02/19/2019
Time: 03:26 PM EDT
Your letter to the bugman: There is a group of about 15 of what appear to be butterfly chrysalides, but I have no idea what they are.
They are about 3/4 inch long and found on the south side of the house attached to the gutter. The house borders on a canal. I found them on 2/19/19.
How you want your letter signed: Sharon 1015
Dear Sharon 1015,
This is not a butterfly chrysalis. It is the cocoon of a Bagworm, a moth in the family Psychidae. The larvae are known as Bagworms because they construct a shelter, the bag, and they enlarge it as they grow, eventually pupating inside the bag.
Letter 2 – Bagworm
Yet more nature via Christmas trees
Hi Bugman!
Your site is AWESOME! We use it for reference a lot. We sent a photo of one of two cocoons (?) found on our Christmas tree near the crown. We have both in a pyrex dish with plastic wrap punched full of holes on top. Any suggestions?
Bill
Hi Bill,
This is a Bagworm, a type of moth. Females are wingless and legless and do not leave the bag. The males will fly to her. We have an entire Bagworm page on our site.
Letter 3 – Bagworm
Bug Id
Hi,
I found this guy on a tree in my yard yesterday in northern New Jersey. Can you tell me anything about it? Thanks! Love your site!
Debie
Hi Debie,
This is the first time we’ve gotten a good image of the caterpillar that lives in a “bag” known as a Bagworm.
Letter 4 – Bagworm
Help identify a cocoon/chrysalis
I’m hoping it’s possible to identify chrysalis. I’ve searched high and low for a guide and can’t find one. I also searched your website for caterpillar’s and moths and found that you do identify some chrysalis in addition to the insects.
But I didn’t find any that matched this form. Location: I came across this one in Surry County, North Carolina attached to a sycamore sapling in the floodplain of a creek. Surry County is in the northwest piedmont/foothills region on the border of Virginia.
Julie
Hi Julie,
This is a type of moth known as a Bagworm. We should probably include a link from our moth and caterpillar pages to our bagworm page.
Letter 5 – Bagworm
cocoon
Hi. I just came across this cocoon hanging from a dead blackberry bush I think. It is about 1 1/4 inches long. The webbing is covered by tiny sticks. Can you tell me what species it belongs to? Thanks,
Marcelle G.
Bayou Segnette State Park
Interpretive Park Ranger
Hi Marcelle,
As an Interpretive Ranger, we are giving your letter a high priority as it is very important to be able to inform the visiting public. This is a type of moth known as a Bagworm. Your photo is stunningly dramatic.
Letter 6 – Bagworm
Subject: Unidentifiable Bug
Location: Gillespie County Texas
August 2, 2017 6:15 pm
We located this bug hanging on a vertical metal fence column in the Texas hill country west of Austin (Gillespie County). It’s mouth was very firmly attached.
It does not appear to be a cocoon. The spines are dark brown and Woody in appearance. It is 3″ long and 1″ wide at its broadest point. Found in July.
Signature: M. Reynolds
Dear M. Reynolds,
This is a Bagworm, the caterpillar of a moth in the family Psychidae. Bagworms construct protective covers from silk and bits of the plants upon which they are feeding and they eventually pupate inside the bag which becomes the cocoon.