Treating Browntail Moth Rash

If you happen to come in contact with the stinging hairs of a browntail moth caterpillar while walking in the woods, wash your clothes and take a cool shower as soon as possible. After a few hours, you may get a rash that is similar to poison ivy’s: itchy, blistered, and swollen skin. Most people experience a localized rash that lasts from a few hours to several days. Those with more sensitive skin can get a more severe rash, lasting up to several weeks. Take Benadryl or apply hydrocortisone cream to the affected area to relieve symptoms. Also, grab a bar of our Poison Ivy Soap, which works well for calming browntail moth rashes as well! Difficulty breathing is also possible after exposure and can lead to more serious problems, if hairs are inhaled. If you’re having trouble breathing, seek medical attention immediately.

When And How To Spot Them

The greatest risk for exposure to these tiny toxic caterpillars is between April and July when they are in their third larval stage. However their toxin can remain stable in the environment for one to three years and may become airborne if disturbed.

Browntail moth caterpillars have a dark brown body with a segmented white stripe running down each side and two noticeable red spots on their back. Younger caterpillars may lack the white stripes. Their bodes which grow to about 1.5 inches in length, are covered in toxic, barbed hairs.

Adult browntail moths have snow white wings, with a wingspan of approximately 1.5 inches and a tuft of dark-brown hair on the tips of their abdomen—hence their name. (This is in contrast to the yellow tip of the similar Yellow-tail moth.) The adult moths fly at night, during July and August, and are highly attracted to light, especially between the hours of 10pm-2am. It is important to note that adult browntail moths are not a danger as their hair is not toxic. But if you do happen to see them, there is a good chance that their caterpillars will be close by, so be on the look out and take precautions.

Browntail Moth Caterpillar Look-a-likes

Browntail moth caterpillars are commonly confused with their long brown-haired look-a-likes: the Eastern Tent and Gypsy Caterpillars. Here’s how to tell the difference: Browntail moth caterpillars have white tufts that run alongside their bodies, but Eastern Tent caterpillars have a white stripe that runs down the center of their back and have blue spots that resemble the “eye” in a peacock feather along each side of the stripe. The gypsy moth caterpillar has prominent knobs with hairs on each side and pairs of blue-and red-spots along its back. These two look-a-likes aren’t as harmful as the brown tailed moth caterpillar, but the gypsy moth is also known to cause skin irritation and damage to trees.

How To Minimize Exposure To Browntail Moth Caterpillars

The first line of prevention is staying away from heavily infested areas, but those are not always known. It helps to wear long sleeves and pants of tightly woven fabric to make it more difficult for the barbed hairs to get stuck in your clothes. Tucking pants into socks also helps.

If you live in an area where there is a large population of browntail moths, wear a mask while raking, mowing, or weed-whacking. This will help you avoid inhaling hairs that may get stirred up. Do yard work on damp days, when the moisture levels are high, to prevent the hairs from becoming airborne. Wipe down or rinse off lawn furniture before using. Avoid drying your laundry outside during the spring and summer months so that clothing, towels, and bedding don’t get covered in the hairs.

Pets or clothing may also transport these barbed hairs into the house. Give your pets a quick brush-off before they enter—especially after a walk in the woods (or rolling outside) in the months of June and July. Be sure to do the same for yourself! Before coming in from outside, swipe your clothes with duct tape or a lint roller to pick up any loose hairs. (Doing this may also pick up ticks that have clung on for a ride! See more helpful hints here.) 

A Danger To Farms And Gardens

The Browntail moth is a health concern for farms, gardens, and forests as well. Browntail moth caterpillars overwinter in webs at the top of trees. In spring, as buds begin to pop open, these hungry caterpillars infest trees and feast on the foliage of hardwood and shrubs including: oak, apple, crab apple, cherry, rugosa rose, hawthorn, and beach plum. They have the capability of defoliating trees twice per season, causing considerable stress to trees. Voracious caterpillar feeding such as this may inhibit plant growth, lead to branch dieback, and even cause death. 

DIY Browntail Moth Management

Prevention is key to curtailing widespread outbreaks. The best way to rid your garden or yard of browntail moths is to monitor and remove any visible moth nests. Winter webs are usually positioned on the ends of tree branches (as pictured above). They are made out of white silk that has been tightly wrapped around leaves and branches (as pictured below). Web clipping is advised between October and mid-April, before caterpillars emerge from winter webs and begin feeding on new leaves. Clip any webs that you can safely reach. Avoid clipping near hazards such as power lines. Leave the hard-to-reach ones for a professional. Once removed, dispose in the trash, burn, or soak in soapy water for an extended period. If you miss the window of web removal, insecticides labeled for controlling caterpillars are often effective if applied consistently before late May. Consider hiring a licensed pesticide applicator if needed.

Browntail Moth History

You may already be familiar with this threatening creature—especially if you live in the northeastern US. They were accidentally introduced to Massachusetts from Europe in 1897 and quickly spread. By 1913 this public health nuisance had swept across New England and as far north as Nova Scotia (and even south, into Long Island).

Have you ever seen the browntail moth or suffered from its rash?

Let us know in the comments below!

Our “Poison Ivy Soap” helps browntail moth rash too!

Poison ivy itch relief in a soap! An old Native American remedy for poison ivy calls for making a paste from the crushed leaves and stems of the jewelweed plant, also known as “touch-me-not.” Fortunately, you don’t need to hunt down jewelweed to get relief.

Natalie LaVolpe is a freelance writer and former special education teacher. She is dedicated to healthy living through body and mind. She currently resides on Long Island, New York, with her husband, children, and dog.

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