Browntail Moth Control: How to Get Rid of Browntail Moths

This article is a general browntail moth control guide. Using the suggested products and methods will help you control browntail moth populations completely. Follow this DIY guide and use the recommended products, and we guarantee 100% control over browntail moths.

The browntail moth is an invasive pest mainly found on the coast of Maine, Cape Cod, and parts of Massachusetts. Many homeowners do not consider this pest an issue because its adult white moth form can be beautiful to witness, while the larvae or caterpillar form creates a nuisance in vegetation.

The caterpillars of these pests are voracious eaters of broadleaf trees and shrubs, especially in the spring. Heavily infested foliage is weakened by the loss of leaves, consequently vegetation growth is poor, leading to possible plant death. The caterpillar of browntail moths also releases irritant hairs into the air and on multiple surfaces, which can cause skin irritations similar to those of poison ivy and respiratory issues.

The hairs of these pests can continue to cause problems for several years after being shed. This is particularly an issue as mowing and other yard activities throughout the spring and summer months increase this unpleasant encounter for homeowners. The caterpillars live in large groups, forming tents, contributing to the spread of these painful hairs. Therefore, taking control of browntail moth populations at the first sign of activity with the recommended products and tips listed in our DIY guide is best.

Identification

Before proceeding with treatment, you must ensure that the pest infesting your yard is a browntail moth. Misidentification can lead you to use the wrong or ineffective insecticides, which can waste your time and money. Refer to the following traits to know what adult browntail moths and browntail moth caterpillars look like:

• Adult browntail moths are white with tufts of brown hairs on the end of their abdomen, hence their name, and have a wingspan of 1.5 inches.
• In their caterpillar form, they have dark brown colored bodies with one broken, white stripe on both sides of their body.
• The caterpillar has painful hairs covering its body and two distinct orange-to-red spots on its back towards the tail.
• Browntail moth eggs are laid in masses within brown-colored egg sacs on the underside of leaves, and they are covered with brown hairs from the adult browntail moth.

Use the image and description above to help you correctly identify a browntail moth or browntail moth caterpillar. If you are unsure of the pest infesting your plants, take a photo or bring it in a sealable plastic container to one of our store locations. By contacting us by phone, email, or in person, we can suggest the appropriate form of pest control and products to quickly control the infestation you are encountering.

Inspection

Once you have confirmed browntail moths on your property, you can proceed with the inspection. Throughout this process, you determine where to apply your insecticides and avoid unnecessary applications, helping to increase elimination efforts and minimize cost.

Where to Inspect

Browntail moth caterpillars feed on the leaves of various broadleaf trees and shrubs from April to late June. Oak, apple, cherry, crabapple, hawthorn, blackthorn, bramble, and other fruit trees are most commonly infested with these pests.

From mid-July to August, adult browntail moths are found mating and laying their eggs on the underside of leaves within trees and shrubs or on man-made surfaces such as fences. During the winter, look for tent-like webs wrapped around leaves. You will know these are brown-tailed moth caterpillars and not tent caterpillars since tent caterpillars are active during the spring and not the winter, like brown-tailed moth caterpillars.  

What to Look For

Eggs will hatch from August to September, and the browntail moth caterpillars will feed on the foliage, turning the leaves brown. As moths, they are attracted to light in their adult forms and are often seen flying around at night from July to August.

In winter, these caterpillars weave tightly wrapped web-like tents around leaves at the tip of the tree and shrub branches or between leaves. They hibernate during the winter and emerge in late spring (April) to feed on the upper side of available leaves. These pests can devour leaves at the first sign of emergence.

In the second half of June, the browntail moth caterpillars begin to pupate, turning into a black cocoon. Towards mid-July, an adult browntail moth will emerge from the cocoon.

Treatment

Before proceeding with treatment, make sure you are wearing personal protective equipment (PPE) since you can be harmed by shed caterpillar skins, abandoned nests and egg sacs, cocoons, and the pest itself, as hairs are found on these objects.

Brown tail moths and caterpillars are active at two times of the year. To get rid of browntail moths and their caterpillars, it would be best to use permethrin or pyrethrum-based insecticides from May to June to control their larvae. Applications from July to August will help control adult breeding activities, fix caterpillars to go into hibernation, and hatch a second batch of caterpillars from their eggs.

Step 1: Prune Branches and Leaves

From October to April, prune infested parts of the tree and shrub branches, limbs, and leaves. Pruning during these periods helps to minimize population growth, control nests and food sources, stimulate plant growth from previous caterpillar feeding activities, and avoid unnecessary contact and the spread of their harmful hairs.

Their webs are durable and allow the pest to survive even if not in its previous nesting site. For this reason, you must collect nests with a glove-covered hand and soak them in soapy water for several days before throwing them away in the outdoor trash can.

Avoid pruning too many branches, which may cause unnecessary stress for your plant.

Step 2: Spray Supreme IT to Control Caterpillars

Supreme IT is a pyrethroid insecticide that kills and repels over 70 types of pests within your home's ornamental plants. Though not specifically mentioned by name, this product is labeled to control leaf-feeding caterpillars, which is essentially what a browntail moth caterpillar falls under. Once this product has dried, it will provide a long-lasting residual to keep killing browntail moth caterpillars for up to 90 days.

Determine how much Supreme IT to use by measuring the square footage of the treatment area. To do this, measure the length and width of the treatment area in feet, then multiply them together (length X width = square footage). Apply 0.125 (1/8) to 0.25 fl. oz. (1/4) of Supreme IT per gallon of water per 1,000 sq. ft. of ornamentals.

Since browntail moth caterpillars are typically found in elevated spaces, we recommend mixing and applying this solution with a 20-gallon hose-end sprayer.

To mix, remove the reservoir from the nozzle. Check that the sprayer control valve and water pump are off before attaching the spray tank. Attach the hose sprayer nozzle to your garden hose, then add the proper amount of Supreme IT. Fill the reservoir with enough water to treat the entire application site. Reattach the filled reservoir to the nozzle, then turn the water back on.

Push forward on the control valve to spray your mixed solution. Pull the valve back until it's in the off position. Once your solution is mixed, spray the leaves on all foliage and trees on your property. Be sure to spray underneath the leaves as well. To spray elevated areas, remove the spray tip to produce a long-reaching stream.

You may spray non-bearing fruit and nut trees and ornamental trees with Supreme IT. Non-bearing fruit and nut trees are those that will not produce a harvestable crop during the season of application nor apply this product to any plant grown for consumption.

Step 3: Apply Flex 10-10 to Control Adult Moths

To get rid of adult moths, you will need to make a space spray application with a fogging insecticide like Flex 10-10.

Flex 10-10 is a synthetic pyrethroid insecticide made to control a variety of pests by interfering with their nervous systems, leading to muscle spasms, paralysis, and death. Formulated with 10% permethrin and 10% piperonyl butoxide (PBO), this product helps to control moths, including adult browntail moths, even though it is not mentioned by name on the product label.

We recommend you apply this product with a ULV fogger or mosquito misting system such as the Tomahawk TMD14 Backpack Sprayer.

To control browntail moths in your home's yard, a 0.09% emulsion of this product (equivalent to 1.66 g of product per 100 cubic meters) should be applied to treat every 1,000 cubic feet of space. To achieve that concentration, you can mix 64 fl. oz. of this product into 55 gallons of water.

Determine how much Flex 10-10 to use by measuring the square footage of the treatment site. Measure the length and width of the treatment site in feet, then multiply (length X width = square footage).

Fill the sprayer reservoir halfway with water, add a measured amount of Flex 10-10, then pour in the remaining half of the water. Tighten the tank lid until secured, then agitate until the solution is evenly mixed.

Pump the primer bulb 3 to 5 times, then adjust the engine's choke position to UP and move the throttle into the ON position. Pull the engine cord until it starts, then move the engine's choke into the DOWN position.

Once you have mixed your solution, apply the solution as a fog or mist in the desired treatment spaces. When applying to foliage, cover over and underneath the leaves. This application will treat flying pests that come into contact with the mist.

Do not allow people and animals to enter treated areas until vapors, mists, and aerosols have dispersed and the spray has dried.

Prevention

Once browntail moths and browntail caterpillars have been controlled, you will need to take preventative actions to ensure they do not return to your home yard and plants. Listed below are some suggestions to follow to prevent browntail moths and browntail moth caterpillars:

• Wait until leaves have fallen in the winter season before pruning away limbs, branches, and leaves covered with browntail moth webs. Pruning at other points of the year can be excessive and cause unnecessary stress to plants in active growing seasons.
• After each use in the outdoor site, clean application and other yard equipment, such as browntail moth hairs, can be evident years after the presence is eradicated.
• Mow your turfgrass when it reaches a height of 3 inches to disturb any traveling browntail moth caterpillars and leftover hairs.
• Rake fallen leaves and other plant debris to discourage browntail moths from traveling to your property.
• Water plants with an inch of irrigation to prevent hair residue and disturb any breeding browntail moths. On man-made surfaces, water it down during calm weather to stop hairs from becoming airborne.
• Make quarterly applications with Supreme IT to control browntail moth caterpillars and other pests throughout the year. Treat present adult moths with Flex 10-10 until the population is controlled.

Key Takeaways

What are Browntail Moths?

• Browntail moths are invasive moths with toxic hairs in adult and larvae forms. These hairs can continue to harm people for several years, even after they are shed.

How to Get Rid of Browntail Moths

• Browntail moths and caterpillars can be removed from your ornamentals and yard with pruning throughout the early fall and winter season. To control caterpillars, perform applications with Supreme IT from May to June and then again from July to August. Spray Flex 10-10 when any adult browntail moth is present, but applications are most effective from July to August when adults are breeding.

Preventing Browntail Moth Reinfestation

• Prevent browntail moths from returning to your yard by performing quarterly applications with Supreme IT. Irrigate foliage and man-made structures on calm days when there are no excessive winds to push away hairs and encourage plant growth. Prune overgrown branches and decaying leaves to limit browntail moth attractants.