Lymantria dispar, or the gypsy moth, is a European moth discovered in the US in 1869. These insects are native to Europe, southern Asia, and northern Africa. While not native to the US, they are commonly found in Pennsylvania, New Jersey, New York, and Delaware. Though the caterpillars were brought here with the intention of making silk, these leaf-feeding pests have become a destructive nuisance.

Gypsy moths are dark and hairy, when in caterpillar form. They have lined backs with five blue dots and six red dots. As caterpillars, they can grow between 38mm to 50mm. When they become moths, adult gypsy moths have hairy bodies. Males are grey and small, while females have a wingspread of about 2 to 3 ⅓ inches. The females’ wings are white with black lines and though they have wings, they do not fly.

Gypsy moths are an invasive species. They feed on a variety of plants, and while this normally wouldn’t be a problem, they consume plants on a high scale, which can be devastating. The larvae feed on trees like oak, birch, willows, and alder. The older larvae stages feed on cedar, pine, spruce, and fir. Gypsy moths are particularly destructive to hardwood forests. As they consume plant life, they are destroying the habitat of many native animals. Since these pests are thriving, the repeat infestations weaken and eventually kill of vital trees.

Gypsy moths don’t necessarily breed quickly, but their eggs are resilient. They can overwinter in their egg stage and rehatch in warmer weather. As Spring blossoms, so do the gypsy moth outbreaks. Females can lay between 500-1000 eggs at one time. This can produce an overwhelming amount of offspring. Female gypsy moths lay their eggs underneath tree bark, in shaded areas, or anywhere they can find a flat surface. They have been known to lay their eggs on outdoor furniture and cars as well. You can spot their eggs easily; they are covered with a mass of tan-colored hairs.

Normally, you can spot gypsy moth egg masses from July or August until the following May. Since their eggs can overwinter, it’s possible they can survive the harsh climate. These tannish masses are often found on host trees, or on surrounding flat surfaces.

The common signs of a gypsy moth infestation are defoliation in trees or holes in leaves. Additionally, you can spot egg masses on tree trunks and other flat outdoor services. You can usually find them in groups, and they can cover millions of acres.

The best thing would be to destroy the egg masses, but you must be cautious when doing so. Egg masses can be destroyed by burning or crushing the eggs. First, you must scrape them from the surface of their host tree and then place them into a bucket. You can also kill the egg by filling the bucket with soapy water. Either way, the egg masses must be removed. If you have an infestation and you don’t feel comfortable removing these pests yourself, contact a pest control expert.

While gypsy moths aren’t particularly dangerous to humans, you still shouldn’t touch them with bare skin. Their hairs can cause an allergic reaction, which can be quite painful. Whenever handling gypsy moths or egg masses, take precautions; use gloves and cover yourself.

If you want to avoid scraping egg masses from your trees, here are a few things you can do. Water your trees during a drought. Gypsy moths are drawn to the dry wood – so keeping you trees hydrated can keep them save. Also, increasing soil moisture can help keep these pests away. Place mulch underneath and around your trees to stave off any gyspy moth invasions. Regardless, this invasive species is resilient. If you have an overwhelming infestation, do not hesitate to contact a professional.