Spotted Lanternflies Laying Egg Masses In MD: What You Can Do

MARYLAND — They have survived the heat and rains of summer, along with traps some residents have laid for the pests, and now they're laying eggs in parts of Maryland.

The spotted lanternfly's egg masses will be laid from September through December, a timeframe which gives Marylanders a chance to make perhaps the greatest impact in fighting back against the bug.

While the adult spotted lanternfly doesn't survive the winter, the egg masses do before hatching in the spring. They're visible from now through June.

Invasive spotted lanternflies, first discovered eight years ago in Pennsylvania and confirmed in Maryland, can devastate maple and walnut trees, along with grapes, hops and other crops. Their favorite plant to feed on is tree of heaven.

The egg masses are about 1 inch in size and contain 30-50 eggs. Eighty to 90 percent of egg masses on trees are found 10 feet above the ground or higher, officials say.

In Maryland, spotted lanternflies have been reported since 2018 in Cecil County. The pest has spread to Harford County, and smaller populations have also been found in Baltimore City, and Allegany, Baltimore, Carroll, Frederick, Howard, Kent, Montgomery, Queen Anne, Wicomico, and Washington counties.

A quarantine order first issued by the secretary of agriculture three years ago for Harford and Cecil counties is still in effect, but has been expanded this year to also include: Anne Arundel, Baltimore, Carroll, Frederick, Howard, Kent, Montgomery and Washington counties, as well as Baltimore City, Maryland Department of Agriculture officials said.

Egg masses are easy to identify and should be scraped off. Use a putty knife, credit card, or other firm, blunt-edged tool to scrape. A helpful tutorial on this process is here, courtesy of Penn State Extension.

Spotted lanternflies often lay their eggs on flat surfaces, such as tree bark, rocks, lawn furniture, firewood, boats, RVs, pallets or anything left outdoors, which can be transported to new locations.

Freshly laid egg masses have a light-gray, mud-like covering, while older egg masses change in color to a light tan, resembling cracked mud. Hatched egg masses lose the mud-like covering, exposing individual eggs that look similar to seeds.

The Maryland quarantine restricts moving materials that might contain the spotted lanternfly in any of its life stages, including egg masses, nymphs, and adults. Residents are asked to check backpacks, bicycles, trash cans, lumber and other material before moving it.

To report a sighting of a spotted lanternfly or any egg masses, contact the Maryland Department of Agriculture at (410) 841-5920 or DontBug.MD@maryland.gov.

Spotted lanternflies have a three-stage lifecycle. They’re prolific breeders and lay masses of 30 to 50 eggs in once place. The eggs are covered with a waxy, mud-colored substance called an ootheca that dries and cracks, an effective camouflage. They overwinter as eggs, go through four nymphal development stages (instars) and an adult stage.

The Cornell College of Agriculture and Life Sciences notes that while many photos show them with their wings unfolded, exposing their red-spotted underwings, that only happens when they’re ready to take flight. It’s more common to see adults resting with their black-spotted, pinkish-tan wings folded over their backs. When females are carrying eggs, their abdomens swell to the point they can barely fly.

If you see them, trap them.

New Jersey Patch collaborated with Duke Farms environmental experts to show readers how to make do-it-yourself lanternfly traps. (See the 11-minute step-by-step video below.)

You’ll need:

• 2 plastic 1-gallon milk or water jugs that can be cut with scissors
• 2 one-half-inch thick rubber bands
• 1 22-inch-long piece of 16-gauge metal wire
• 1 24-inch-by-36-inch plastic coated screen, such as a window screen replacement
• 1 2.5-gallon Ziplock bag
• 1 6-inch long piece of all-weather tape
• Hot glue gun and glue sticks
• All-natural string or twine

Here are more things to know about spotted lanternflies:

Although lanternflies usually do not kill plants, they suck out sugars that significantly weaken their hosts and leave behind massive amounts of honeydew — that is, excrement — which is typical of the true bug order Hemiptera.

The honeydew can attract other insects, including wasps, ants and bees, and also cause a sooty mold to grow on the plant, interfering with its ability to photosynthesize and create the energy it needs to survive and grow.

With reporting from Patch editor Josh Bakan.