While we’re all busy fighting a strange new enemy, our landscapes are in the middle of battling a plague of their own—the spotted lanternfly. This invasive new pest has become more and more destructive over the past few years, and now that many of us have more time to spend at home, there’s no better time to fight back. Here’s what you need to know.
What is Spotted Lanternfly?
Spotted lanternfly, sometimes referred to as SLF, is an invasive pest that appeared in southeastern Pennsylvania in 2014. The adults are approximately 1 inch long and are easily recognizable by the Dalmatian-like black spots on their upper wings, visible when the insect is at rest. When the wings are open, the pest is even more distinctive with its bright red and black markings on the lower wings. If they weren’t so destructive, their interesting appearance would make them quite pretty. Unfortunately, they can do some ugly damage to your favorite plants!
The Lanternfly Life Cycle
In the fall, adult spotted lanternflies build an egg mass containing about 30-100 eggs, which they lay against a hard surface—often a tree, deck, or the side of your house. The eggs are protected with a thick coating of mud, which makes them fairly easy to spot if you notice them in time. Unfortunately, many of these masses go unnoticed, and the nymphs hatch in the spring—right around now.
The nymphs mature in four stages. The hatchlings start as ⅛-inch black bugs with white spots and keep this coloring as they grow larger and mature through the next two stages. When they reach the fourth stage, the nymphs are approximately ½-inch long with bright red markings. They typically reach this stage by July, advancing into adulthood from mid-summer to late fall.
Spotted Lanternfly Damage in the Garden
Lucky for us, lanternflies are harmless to people—they don’t bite, and they aren’t aggressive. However, these pests don’t have any natural predators here in Allentown, so they can quickly cause enormous damage to your plants, shrubs, and trees. Like aphids, spotted lanternflies use their piercing-sucking mouthparts for drinking the fluids out of plant material. However, since the insects are much bigger than aphids, they can cause much worse damage, a whole lot faster.
Lanternflies cause serious problems for all plant types, from leaf curling and wilting, to sap loss and black sooty mold infections. They are known to take over entire trees, infesting them so severely the tree needs to be removed entirely to get rid of them. They are a massive threat to gardens, landscapes, and farms—but thankfully, we’re not entirely powerless against them.
Preventing Spotted Lanterflies
Wherever you are in Lehigh County, you’re better off preventing lanternflies before you see them. Right now, all of our landscapes are at risk, and it’s much easier to be proactive than deal with the effects of an infestation.
Scout your property now and in late summer and fall for egg masses. Look for clumps of mud on the hard surfaces around your yard and scrape them off as you find them.
Never move firewood out of your area. Lanternflies are known to hide egg masses in firewood piles—this tends to be how they migrate from one area of the state to the next.
Band trees with sticky bands to catch adults and nymphs—especially tree-of-heaven. Tree-of-heaven (Ailanthus altissima) is the preferred host plant of the lanternfly, but they’re known to infest other trees as well. Using bands is one of the simplest and most effective ways to control lanternfly populations, so band every tree on your property if you can!
Remove tree-of-heaven if possible. If you do have this tree on your property and you have the means to remove it, it may be best to cut your losses and get it done. Like the lanternflies themselves, tree-of-heaven is an invasive species originally native to China. This means the tree-of-heaven is a recognizable food source for the lanternfly—good news for the lanternfly, but awful news for your landscape!
Controlling a Lanternfly Infestation
If you have found lanternflies on your property, start treating affected plants aggressively as soon as possible. Treat affected plants with horticultural oil as a first option, but if the infestation continues, contact us for appropriate insecticide recommendations. Heavily affected plants should be cut down and burned to prevent the insects from spreading to other areas of your neighborhood.
While it’s a bother to deal with pests like the spotted lanternfly, it’s all of our responsibility to help control this invasive pest. Give us a call or visit us at Lehigh Valley Home and Garden to learn more about products that can help you win the fight against these tiny terrors—we’re happy to arrange curbside pickup at our garden center. Please note that while our garden center is closed, our outdoor nursery is currently open, and our staff can assist you onsite in compliance with CDC guidelines.