An adult spotted lanternfly (Lycorma delicatula, above) and a nymph below, red body) in photographed in Pennsylvania. The proliferation of the flies, an invasive species, has caused growing concern …
by Brendan Sample
As spotted lanternfly nymphs continue to spring up throughout Northwest Philadelphia, an increasing number of residents are turning to local botanical institutions and arborists for advice on how to deal with these crop-destroying insects.
Though plenty of information on the pests can be gathered by just searching for them on the Internet, the practical experience of these organizations and individuals can be a greater source of assistance for this relatively new threat.
Local arborist Ken LeRoy, who is part of John B. Ward & Co., Arborists, has said that many of his clients have been contacting him regarding their concerns about the lanternflies. On the one hand, LeRoy feels that the insects are not killing walnut trees, which they seem to prefer in their nymphal stage, and thus may not be quite as significant a threat as they have been perceived. On the other hand, he does realize that the depletion of the trees and other crops could pose a real threat to the agricultural industry.
“There’s definitely a fear of the lanternflies spreading diseases among trees and harming fruit trees, particularly grapes,” LeRoy said. “There’s also a problem when they go from this nymph stage to their winged adult stage, which is when they start to mate.”
In fact, LeRoy even argued that insects like the emerald ash borer have just as much of a negative impact on the environment, if not more. While the ash borer only targets ash trees, its actions have led to the death of those trees and it has been in this area for about six years now.
“The ash borer has been killing all the ash trees in North America, but everyone seems preoccupied with lanternflies,” LeRoy argued. “They’re both invasive and exotic insects, but they’re also small enough that you don’t really see them the way you do lanternflies, but you certainly see the effects they have.”
The most common prevention techniques against the lanternflies have so far been spraying insecticide on trees where they congregate and attaching sticky tape on the trees to catch them.
“I’d definitely recommend using sticky tape technique, as it’s less expensive to apply and potentially more environmentally friendly,” said Luke Hearon, plant protection intern with Morris Arboretum. “If you don’t put cages around them as well, larger animals like birds and squirrels can also get caught.”
While there are certainly proven techniques for dealing with lanternflies after they become a problem, there is also the question of preemptive techniques to keep them from being a nuisance any further. This is a more complicated problem, however, as the lanternflies have not been in the area for long enough to establish a full range of noticeable patterns that could assist with prevention.
“It’s certainly frustrating that there’s not much I can do right now about them because I have to see what they’re attracted to,” LeRoy said. “It’s not ethical to just go to a property and spray insecticide because of one sighting.”
Despite such setbacks, Morris Arboretum is already taking measures to assist with long-term solutions for the lanternflies. The organization will be conducting a study on the sticky tape technique, what other insects it catches and what kind of collateral damage it can do in general. Considering that it is currently a mostly untargeted technique, the arboretum wants to have a better sense as to what exactly they’re catching on their own trees.
With the number of plants that it is already tasked with caring for, Morris Aboretum certainly has a vested interest in trying to control the lanternfly infestation. Beyond providing help for others in examining possible solutions, the arboretum is also looking to ensure that the benefits to the environment outweigh any potential harm.
“That’s sort of the question of the day around here lately,” Hearon said regarding how the arboretum is looking into protecting its own plants from the lanternflies. “We’re ultimately trying to balance any potential collateral damage. We have to question the possible costs and how to responsibly control the lanternflies.”
Brendan Sample can be reached at email@example.com or 215-248-8819.