REGION—A burgeoning invasive species in the southern part of Pennsylvania threatens the agriculture industry across several sectors.
The spotted lanternfly (SLF), native to China and other parts of southeast Asia, first appeared in Berks County in 2014 wreaking havoc on the grape, orchard and logging industries in the area.
In the three years since, it has been spotted in thirteen counties in the southeastern portion of the commonwealth, prompting a quarantine zone which encompasses Berks, Bucks, Carbon, Chester, Delaware, Lancaster, Lebanon, Lehigh, Monroe, Montgomery, Northampton, Philadelphia and Schuykill counties.
Though it has not yet been cited in Wayne County, it is not far off, having breached the southern portion of Monroe.
Wayne Conservation District Forest Specialist Kelley Stewart stated its presence here could severely hinder the county timber industry, even more than is already threatened by the emerald ash borer and hemlock woolly adelgid.
The SLF feeds on the phloem of plants which Stewart described as the sugary energy stores created during the photosynthetic process.
This severely hinders the plant's ability to function.
Information from the state Department of Agriculture note “weeping wounds” may develop on afflicted trees.
These sap secretions can attract other insects to feed on the vegetation as well.
Stewart noted not all the phloem is ingested by the SLF. Waste materials known as “honey dew” can build up on the plant itself and fruits it may produce, making them unsalable.
Moreover, Stewart said the honey dew can cause a sooty, black mold to develop on the plant.
“It's a really big issue,” said Stewart, “It could really be devastating to Pennsylvania.”
How they spread
Despite only being able to travel a few miles by its own merit – what Stewart described as a plant hopper rather than a true flying insect – the SLF feeds and lays its eggs on 70 species of plants and trees, transportation of which, such as through the logging industry, can introduce them to a new area.
Additionally, Stewart noted they're fond of fastening themselves to cars and plastic furniture which unsuspecting travelers may ferry to new locations.
Materials from the Department of Agriculture note the SLF can lay its eggs on any flat surface.
When laid, the clutches of 30 to 50 eggs are aligned in columns of four to seven and caked with a coating akin to mud.
The whole clutch is about an inch long, according to materials from the state Department of Agriculture.
SLF lays its eggs in the fall. The surface layer cracks and falls off over the winter, and the new spawn hatch in spring, said Stewart.
At this stage, education, vigilance, proper reporting and disposal are the best ways to fight the spread of these insects, explained the conservation officer.
Particularly in the winter, before they hatch, locating, removing and disposing of egg sacks is the best way to curtail the SLF's progress.
The state Department of Agriculture recommends double-bagging clutches and/or submerging them in alcohol to dispose of them.
Additionally, the department urges those who may find egg masses to document and report the find.
Pictures can be sent in to the department, or the incident can be reported to the Automated Invasive Species Report Line at 1-866-253-7189.
Stewart noted the wide variety of species on which the SLF feeds and lays its eggs makes it difficult to halt their progress with widespread pesticides.
“There's just no way to chemically treat all these plants,” she said.
She explained the variety of ecologies at play require different types of insecticides/herbicides so as not to harm the positive species in the area.
Another problem with the insect is that it has no natural predators in the area, said Stewart.
She explained that during the SLF lifecycle, it feeds on the Tree of Heaven/Paradise Tree.
Stewart noted experts surmise that in doing so, the bug picks up toxic metabolites which makes it distasteful for birds to ingest.
“Birds would vomit immediately after eating the bug,” said Stewart. Eventually, they learn to leave it alone.
Despite this, Stewart noted conservation experts are looking into the viability of introducing species of parasitic insects to feed on the eggs.
Stewart noted other research into temperature manipulation as population control is also being done.
Response to the SLF
The Northern Tier Hardwood Association announced Tuesday they will be holding an informational meeting concerning the SLF in Mayfield, Pennslyvania on Tuesday, February 27 from 6:30 to 8:30 p.m.
The meeting will be held at the NEET Center, 1300 Old Plank Road in Mayfield.
The organization requests reservations be made prior to the event. Those interested in attending can register at nthardwoods.org.
Additionally, in an effort to prevent further spreading of the SLF, The United States Department of Agriculture (USDA) announced on Wednesday, February 7, it will supply a total of $17.5 million in emergency funding.
According to an article in the Associated Press (AP), $8.7 million will go towards a survey and control program and $7.5 million will fund insecticides and herbicides to manage the problem.
The rest will be put towards public education efforts.
More information regarding the SLF can be found on both the state and federal department of agriculture websites: www.agriculture.pa.gov, www.usda.gov.