Spotted Lanternfly Eggs

by Lynne Pieri-Finn, Fairfax Master Gardener

Lanternfly nymphs

Lanternfly nymphs

I know most of us have become resigned to seeing spotted lanternflies flitting about. There has been an increased interest in stomping on them, as children from Herndon’s NatureFest this past fall can attest. They are enthusiastic stompers. They regaled the Master Gardener volunteers with their efforts, stomping their feet and exclaiming, “I STOMP ON THEM!”

The difficulty is catching them unawares. If approached from behind, they are likely to jump and fly off. Approaching them head-on works well, because they are unable to jump forward or sideways. However, when one sees you approach it head-on, it carefully reorients itself forward to make a quick getaway.

What is a person to do? Is there any remedy for this insect that feeds on over 103 species of plants and excretes a sticky substance over everything? I have a solution. The key is to destroy spotted lanternfly eggs before they hatch. This is best done before they hatch in the Northern Virginia area in late April to early May. But how to find them?

Spotted lanternflies hide their eggs in very clever ways. The female lays her eggs in an inconspicuous location, usually on the bark of a tree. Since the egg masses are grey in color, they mostly pass unnoticed. I searched for egg masses on walks with my dog, but I was unable to find any.

I saw lichens and natural discolorations of bark. I imagined that the lanternfly would prefer smooth bark, although I checked ridged bark as well. No luck. Where were these egg masses?

lanternfly egg masses

Two covered egg masses on Maple tree

My mistake was checking the vertical aspect of the tree trunks of trees and that I did easily enough. But when I looked on the UNDERSIDE of horizontal branches, (think of huge thick branches extending directly from the trunk (picture), there they were! But were they lanternfly eggs?

These masses looked a bit like cement, or patches of grey caulk or putty. They were about 2 to 3 inches (5 to 7 cm) in length (a rectangular aspect) and slightly raised. I scraped one off with my house key and to my surprise, the bits fell down and went all over my clothing. YUCK! I didn’t do that again!

There were dozens and dozens, all on various parts of the underside of a red maple. They seem to like red maples, silver maples and willows, although I have only spotted them (ha, ha) on red maples, which have the particular branching structure they prefer.

Why did I find so many on this one tree? The females like to lay their eggs where other females have laid theirs, sort of a knitting club for lady lanternflies. So once you find the unlucky tree, you have it!

So what to do? I rigged myself a small box with a small plastic trashcan liner. I got a putty knife from my painting supplies (don’t use a credit card…totally gross) and carefully scraped the masses into the box. AVOID WINDY DAYS! If the eggs fall on the ground they are still able to mature, but since lanternflies lay their eggs on the UNDERSIDES of trees, perhaps they know something about keeping the eggs dry and cocooned. Nevertheless, I tried not to let them go on the ground, although some did.

lanternfly egg masses

Uncovered egg masses with some opened

Once in a while, I found what looked like a railroad track of tiny eggs. These uncovered egg masses have a 10 percent lower hatch rate on average, but hatch they will. The female may have been under pressure (predators, weather, time) and didn’t have a chance to cover the eggs. I scraped these off, too.

CAUTION! Do not, and I repeat, do not, attempt to remove lanternfly eggs higher than you can reach. Ladders are not good and dangerous, too, because often you are working in mud or on exposed tree roots. Let those egg masses be. I learned this the hard way, so I’m warning you!

Do you know that each egg mass you remove destroys 30 to 50 lanternfly eggs? On a heavily infested tree, you could destroy upwards of 2,000 eggs. That’s 2,000 less lanternflies floating around. It also saves you from some stomping, wasted effort, time and strange looks from passersby.

As far as the eggs themselves? They look like tiny black seeds, not distressing at all, although if you wait too long in the season and they “ripen” and make a squishing, popping sound when scraped. Who wants that? Not me!

Once you are done scraping for the day, put some rubbing alcohol into the bag and squish it around. Then seal the bag and dispose of it.

So get out there in nature, weekend warriors, use your eyes on those walks, look for trees with a certain aspect now (March) before they emerge. Take out some of those lanternflies before they hatch! But please, be careful, there is always next winter, right?