Also known as the Spongy Moth, the Gypsy Moth is a destructive pest that awakens every summer and wreaks havoc on trees all across Eastern Pennsylvania.
You can spot these pesky creatures overwhelming various tree species across our great state in their caterpillar form, where they are most destructive.
Gypsy moths are a widespread pest that has infested Luzerne and Lackawanna Counties since 1933 and has since spread south and westward to Lehigh and Montgomery Counties.
Though these moths may seem harmless, this invasive species has had devastating effects on our foliage.
If you suspect you may have gypsy moths on your property, here are a few things you should know about gypsy moth control to protect yourself and your property.
What Are Gypsy Moths?
Gypsy moths, scientifically known as Lymantria dispar, are invasive insects originally brought to Massachusetts in 1869 to explore their potential for silk production. Since then, they’ve become one of the most destructive pests in the eastern United States.
These moths pose a serious threat to hardwood trees like oak, birch, and maple. One female gypsy moth can lay a single egg mass containing 400–600 eggs, and they’re not picky about where they lay them; tree trunks, patio furniture, vehicles, and even house siding are all fair game.
When the eggs hatch, the caterpillars emerge in large numbers and quickly strip leaves from trees, weakening them and leaving them vulnerable to disease and other pests.
While birds and small mammals feed on gypsy moths, these natural predators are not enough to control outbreaks. As a result, gypsy moth populations continue to grow, causing extensive environmental damage each year.
Why Are Gypsy Moths Dangerous?
Since 1869, gypsy moths have defoliated a million or more forest areas annually. On a smaller scale, they can cause extensive damage to backyards and urban areas, destroying foliage that might have been standing for decades on your property.
Additionally, the sheer scale at which gypsy moths can reproduce can make an excursion to your backyard uncomfortable when there are literally hundreds of caterpillars climbing amidst the trees.
What Do Gypsy Moths Look Like
Identifying gypsy moths is easiest during their caterpillar stage when they emerge in huge numbers, which is also when they do the most damage. Here are some ways to spot a gypsy moth in person.
- Caterpillars grow up to 2 inches long and are covered in hairs.
- They have a distinctive pattern of five pairs of blue dots followed by six pairs of red dots running down their backs.
- Male moths are gray-brown with feathery antennae and can fly.
- Female moths are larger, creamy white in color, with dark, wavy markings on their wings. Though they have wings, they cannot fly.
- Egg masses are fuzzy, tan or light brown, and about the size of a quarter. They’re often found on flat surfaces such as tree bark, outdoor furniture, fences, and even vehicles.
How to Identify Gypsy Moth Damage
The most obvious sign of gypsy moth damage is defoliation: trees that are suddenly bare of leaves during spring or early summer. Other signs that your trees have been destroyed by gypsy moths include:
- Skeletonized leaves, where only the veins remain
- Brown or scorched-looking foliage mid-season
- Silken threads hanging from trees or branches
- Dark droppings (frass) under affected trees
- Clusters of egg masses on trees, furniture, or building exteriors
Heavily infested trees may look completely dead by early summer but could regrow foliage later in the season. However, repeated defoliation over several years often kills the tree.
7 Ways to Prevent Gypsy Moths
If you want to keep gypsy moths from destroying your backyard and taking over your property, here are seven preventative pest control tips.
1. Keep your Lawn Clean.
Gypsy moths like to lay their eggs on multiple surfaces. Aside from susceptible host trees, they will house themselves in debris, on stumps, and other unused items. If it is a flat surface, gypsy moths will lay their eggs on it. The best way to keep them from getting cozy is to keep your yard clear of enticing areas.
2. Keep An Eye Out For Egg Masses In Your Yard.
Though it’s important to remain vigilant when keeping pests out, removing everything from your backyard is impossible. The next best thing is to keep on the lookout for egg masses. Check woodpiles, stone walls, and lawn furniture often. Should you spot egg masses, scrape them off carefully and douse them with boiling water. It’s not enough to just remove them. Also, be cautious when removing them; make sure they do not touch your skin.
3. Check Your Car
So, you’ve been keeping an eye on your yard and you haven’t spotted one gypsy moth mass. There are other areas you may not have considered. Believe it or not, egg masses can be found in your car. Also, check your house siding, sheds, or other structures. Remove the egg masses in the same way as described above to put an end to them.
4. Plant Different Trees
Another way to discourage gypsy moths from invading your property is to plant trees they are less likely to go for. These invasive species prefer hardwood. The best alternative would be to plant other trees, such as ash, locus, dogwood, sycamore, balsam fir, and mountain laurel.
5. Minimize Contact
Should you have to deal with this unfortunate pest, be very careful. Many people are allergic to gypsy moths and touching them can cause a serious reaction.
If you are experiencing an infestation, be sure to wear long sleeves when leaving the house and take steps to dry your clothes inside. Additionally, wear gloves when handling them. Should you come into contact with them, use the proper ointments like Cortisone to stop the reaction.
6. Rely On Birds, Wildlife, And Natural Causes
Let’s be clear – you don’t want to replace one pest with another. However, encouraging natural predators is a good way to keep this invasive species away, and they can be naturally exterminated.
Also, though we have no control over it, a naturally occurring virus called ‘wilt’ and a fungal pathogen called entomophaga maimaiga, are causing the collapse of heavy infestations. These have had a great effect on the fight against this invasive species.
7. Call An Exterminator
When it comes down to it, a major infestation can be difficult to deal with. While chemical insecticides do exist that can kill gypsy moths, they can cause harm to other plants and wildlife as well.
If you are faced with an invasive species problem, consider contacting a pest control expert to oversee and handle the issue quickly and with little harm to other plants and animals.
Gypsy moths are not only a danger to your home and family; they are destroying our native foliage. Take the proper steps to safeguard against this invasive species and keep them from your property.
FAQs
When do gypsy moths typically hatch?
Gypsy moth eggs hatch in early to mid-spring, typically around April or May, depending on local temperatures. The caterpillars then begin feeding immediately.
Can gypsy moth caterpillars harm humans?
Yes, the hairs on gypsy moth caterpillars can cause skin irritation, rashes, and in some cases, respiratory issues, especially for people with allergies or asthma. Avoid touching them with your bare hands.
How fast can a gypsy moth infestation grow?
Very quickly. A single female can lay up to 600 eggs, and if even a few survive, populations can explode the following season.
Do gypsy moths prefer certain trees?
Yes, they prefer hardwoods like oak, maple, birch, and poplar. Repeated feeding on these trees can lead to serious decline and death if not addressed.
