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Chester County Press

Experts, action committee meet to discuss problems, solutions

06/20/2017 02:35PM ● By Richard Gaw
By Richard L. Gaw
Staff Writer

For the third time, the phorid fly, the pesky nuisance that has infiltrated a significant portion of the Harrogate North community in Landenberg and other parts of southern Chester County, went on trial last Thursday afternoon, as State Sen. Andrew Dinniman and Rep. Eric Roe met with local residents and experts on phorid fly research to get an update on the fly's continued presence, and scientific research related to its possible eradication.
Six representatives from the 247-member Phorid Fly Action Committee (PFAC), gathered around a table at the New Garden Township Building on June 15, side-by-side with representatives from the Chester County Department of Agriculture, the county's health department and conservation district.
The meeting also invited Eric Toedter of Kaolin Mushroom Farms, who has been studying the phorid fly migration and breeding patterns as part of his role with the American Mushroom Institute Integrated Pest Management Group, and Dr. Nina Jenkins, a senior research associate in Entomology at Penn State.
Dinniman, who serves on the Senate Agriculture and Rural Affairs Committee, was instrumental in establishing a $100,000 grant from the Commonwealth to the Department of Agriculture at Penn State to to study ways to control and combat the phorid fly infestation in the region.
When Dinniman first addressed the phorid fly problem nearly two years ago, he was the lone official doing so.
“When we first addressed this problem, no department would take responsibility,” he said. “Every one said it was someone else's responsibility. We want to put into place a program that attempts to deal with this difficult situation, and it's not so easy to solve, is it? Let's see what some of the updates are in terms of research, and then we can see if that research can tell us whether it's working or not working, whether it's new ideas on prevention or at least a diminishing of the problem.”
At first, the news coming from residents was a near duplication of the two previous meetings Dinniman had held at the Harrogate North community, and it wasn't good. The presence of the fly is not going away, said several PFAC members who gave updates on the various home remedies they have brought to their homes, which have included insecticide sprays, and the application of sticky fly paper around the home.
Even worse, what had generally been considered a rumor in southern Chester County has now been confirmed: Phorid flies are not only being reported in Landenberg, but elsewhere in the region.
“We are the only home that has attracted phorid flies, and we have trapped over 500,000 phorid flies in our home,” said Oxford resident Georgie Emery, who lives with her husband Paul in a 48-home community. “In one two-hour period, we vacuumed over 2,000 flies. We're retired, and we don't feel like doing this.”
Two residents of the newly-built Harlowe Point in Landenberg said that the flies have reached their community, and Pete Thomas, a resident of Kennett Square Borough, reported the same news.
PFAC member Barb Runkle said that the presence of the flies have caused a tremendous emotional stress for many Harrogate residents, which she said has led to two couples selling their homes in the development.
On May 1, as she was sprinkling cedar chips around the soil area that abuts the front foundation of her home, Runkle saw a scourge of phorid flies working their way up through the soil. She poured a highly-concentrated termite solution in the area. During treatment, there were no flies seen in the Runkle home, but after a two-week period, the flies re-emerged. She and her husband have had all of the mulch removed around their home and applied 14 gallons of bacillus thuringiensis israelensis (BTI) solution to the foundation area, as well as planted insect repelling flowers, and had their lawn treated with flea and tick application. Still, the flies are coming, she said.  
Runkle's experience is part of the warfare that's been raging in Harrogate and in other selected pockets of southern Chester County for several years – a persistent condition that has turned citizens into part-time scientists, and while the issue of the phorid fly in the region is a story top-heavy in hypotheses, it is sadly one still very short on definitive answers.
What is known is this: From egg to adult, phorid flies emerge underground in the mushroom facilities. There, they feast on the edible component of the mushroom called mycelium, which is the vegetative part of a fungus or fungus-like bacterial colony that is grown in mushroom facilities.
And yet, one question, repeatedly asked by local residents throughout the meeting and over the last several years, remains: What is so great about our homes and neighborhoods in the proximity of these mushroom houses that it compels the phorid fly to leave these facilities and invade us?
"We know that the flies are attracted to the light, and they impact themselves on the windows [of the farms], because they want to go out," Jenkins said. "Quite possibly, they're going to the neighboring properties, but we don't know why. There's really nothing tasty for them there. It's a mystery as to why they would want to go to residential neighborhood, when the room next door is filled with the next crop, which is a far better life strategy."
The work to find the answers goes on. As part of Penn State's research, Jenkins said that her department is currently monitoring 17 farms in Pennsylvania, one of which is Kaolin Mushrooms in Avondale. Sticky card placements throughout the houses measures daily volume and egg laying patterns.
Jenkins said that she is not aware of any similar problem occurring at any of the other 16 farms involved in the study. Meanwhile, Penn State's research in finding out more about the phorid fly patterns continues, and will soon involve exploring the use of technology and pesticide products, and evaluating the fly's migratory and mating patterns, in an effort to find out why they leave mushroom farms.
"We're going to be putting sticky traps outside the mushroom houses, so that we can see where they are moving outside," Jenkins said. "We're trying to get a handle on where they are going and what they might be doing, because we really don't know."
To contact Staff Writer Richard L. Gaw, email [email protected] .