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Chester County Press

The phorid fly in Chester County

11/15/2016 12:51PM ● By Richard Gaw
By Richard L. Gaw
Staff Writer

At one-eighth of an inch long, the phorid fly breeds in, and feeds on, moist and decaying organic matter, as well as in unsanitary areas, and it is widely known throughout entomology as a carrier of disease-causing bacteria.
For the past several years, they have moved into the immaculately pristine home owned by Colin Carson and his wife, Marion, in the Harrogate North community in Landenberg.
Nearly every morning this fall – when the infestation of the phorid flies are at their peak – Carson has applied a mixture of water and Dawn dishwashing liquid to the side of his house.
An illuminated FlyWeb light glows on a wall in the home's main living space, sharing the room with with framed photographs of smiling children and grandchildren. It is one of six lights placed throughout the home, and its job is to capture the microscopic insect through a stick flypaper, which Carson changes constantly.
Carson has more arsenal -- what he calls his "box of tricks" – seen in the form of bottles and jars of insecticides like ExciteR, Bifenthrin, lavender oil and neem oil that he blends together like a weekend scientist and applies in spray form around the exterior of his house.
He points to the box.
“This is not what I envisioned doing when I retired,” Carson said.
For the past three years, Avondale resident Paul Morgan, a father of four, has dreaded October's arrival. Phorid flies gather at windows in the home. They crawl on the kitchen counter. They appear close to his childrens' beds, and they cling to their toothbrushes before they go to sleep at night. During the time between early October to the first frost, it is not uncommon for Morgan to spend as much as 45 minutes every night vacuuming up dead phorid flies, and on days when he is not at work as a dairy farmer, he spends as much as four hours vacuuming.
“Usually when I come home, it's 'Hey, Daddy's home,' but lately, I can't help them with their homework, because I am upstairs, vacuuming,” Morgan said. “You kill a hundred of them, take a break, come back, and there are 150 more of them. We are not dirty people, and yet this has made us feel dirty.”
On Oct. 25, Morgan was one of 180 people who attended a public forum at the Avondale Fire Company. He heard the testimonies of several residents of southern Chester County, who shared their stories with elected officials about their living with phorid fly infestation. Also there was Pa. Deputy Secretary Fred Strathmeyer, Jr. of the Pa. Department of Agriculture; and David Beyer, an entomologist with Penn State and one of the nation's leading experts on phorid fly eradication.
The forum was a revelation for Morgan, a small sliver of light through the nightmare. Now, he realized; he was not crazy, and he was far, far from alone. 
Phorid fly sightings, once confined to the epicenter of the Harrogate North community, are now being regularly reported in Hockessin, West Grove, Avondale, Oxford and Kennett Square.
Recently, ten Harrogate residents formed the Phorid Fly Action Committee [PFAC], whose intention will be to educate residents, government officials and government agencies about the phorid fly. In its mission statement, the PFAC "welcomes all residents who are suffering from this fly invasion of their homes. It supports and takes action in defense of our property, offer and assist government agencies, state officials, community organizations and academic research in the eradication of this infestation."
The seeds of this committee can easily trace its steps back six years ago, when Harrogate North resident Lou Taylor first reported the news of the phorid fly presence at his home, to New Garden Township.
On Feb. 16, the news became public, when the New Garden Board of Supervisors hosted more than 50 residents of the development, who told the supervisors that they were fed up with living in a nightmare.
Calling the infestation "a serious issue in our community,"  Les Clark, the president of the Harrogate North Condominium Association, asked the board for help in helping to eradicate the fly from Harrogate, a problem that has now spread to a majority of the community's 124 homes.
On May 19, a gathering of agricultural experts met with State Sen. Andy Dinniman and residents of the Harrogate North community, to discuss possible solutions to the increasing presence of the phorid fly in the development. The key take away from that meeting was that although long-term solutions to eradicate the phorid fly are being studied at Penn State -- a five-year, $1.4 million grant from the USDA-- that more money is needed to find more answers. The project's funding dries up next year.
“We're hoping to find money to keep the study going, because we're going to need additional funding to continue to screen products,” he said. “It's really a matter of finding the right product at the right time, because these flies are small and sneaky, and they build up resistance very quickly. We have to find products in order to give the flies less of a chance to be resistant to what we're using.”
David Beyer, one of the nation's leading experts on phorid fly eradication, told Dinniman that Penn State is the only entity currently doing extensive research on the phorid fly, but with no assurance of another grant, the study is appealing to the Mushroom Institute to fund a technician, in order to continue maintaining and studying the insect in the lab.
Time and money is not the only roadblock, the PFAC group said. Ownership -- or lack, thereof -- is another problem. Despite the group's efforts to get local, regional and state conservation agencies and businesses to climb on board, too many people are telling members that the phorid fly does not fall within their "list" of insects to study and regulate.
Whether it is passing-the-buck, kicking the can down the road -- or whether no one truly knows when, how and who will eliminate the phorid fly from southern Chester County -- remains anyone's guess, and yet, in the continuing search to find answers, one industry keeps popping up. To some, the mushroom growing industry in southern Chester County has been judged to be the fall guy -- the scene of the crime -- while to others, it is looked at as a future partner who will bring solutions.
"There is a culture in southern Chester County that the mushroom houses were here before we were, and that we need to put up with this, because this industry built this area," Runkle said. "While I understand perfectly that the mushroom homes contribute economically, we contribute economically, too. We contribute through our taxes, and we contribute to the school system. Not to pit people against each other, but in an area where it's okay to have farming operations extremely close to residential areas, there has to be some kind of awareness on the part of the mushroom industry, that we are their neighbors, and they should be helping us."
No matter if it is in the form of a conservation agency, a regulatory group, scientists and elected officials, all PFAC wants is a firm commitment.
"There is no organization, no state or county or township organization who feels as if they own this problem," said committee member Joe Miscione. "If we can get an owner who feels that they have a responsibility to mitigate, cure or eliminate the infestation, we would be on our way to solving the problem. Right now, there's probably not a lot of hope that it will be eliminated, but at least we could mitigate it. The cure could be a long way away." 
In the mean time, PFAC believes that foundational spraying is merely a band-aid on a wound that is only growing larger, one that needs more than just bug sprays and boxes of tricks. The committee is working with the township and Sen. Dinniman's office to try to get aerial spraying done at the community, in conjunction with the Pennsylvania Black Fly Suppression Program. Run by the DEP, the program aims to reduce adult black fly populations to tolerable levels during the spring and summer recreational season, using environmentally compatible methods.
The program involves monitoring and treatment of approximately 1,714 miles of rivers and streams in the commonwealth, and treatments are done by helicopter, using Bacillus thuringiensis israelensis (Bti), a naturally occurring soil bacterium, to selectively target black fly species in the group that bother people. The program currently conducts control work in 39 participating counties, including Chester County.
Ben Russell, the county representative for the Black Fly Suppression Program, told Committee founder Barbara Runkle that there was no firm evidence stating that the treatment would kill phorid flies. Further, he said that while overhead helicopter spraying may not be possible in the Harrogate North community, that treatments could be done with spray trucks. It could be paid for through a $40,000 grant that Sen. Dinniman's office is trying to secure.
While they await news on potential large-scale spraying, the committee has already begun to build its foundation of support, by creating its own Facebook page, "Phorid Fly Community - Public."
A lot has happened, members said, since the time Taylor walked into the New Garden Township offices six years ago to complain about the phorid flies that began to invade his home
"We're focused more on the big picture, not just Harrogate," said David Runkle. "When we found out that the phorid fly has been spreading, we knew that we had to begin trying to get the word out. It's important for everyone to inform others just how widespread this problem has become."
"I sent an e-mail recently [to members], and wrote that it is time to start rattling cages," Barbara Runkle said. "I wrote that it's time to start calling, and that's what we did. We had people begin calling down the list [of agencies], and I told them, 'Even if they can't help you, lodge a complaint, and keep going.'"
Note: Over the next several months, the Chester County Press will continue to report on the growing presence of the phorid fly in our community.
To contact Staff Writer Richard L. Gaw, e-mail [email protected]

To learn more about the phorid fly, join “Phorid Fly Community – Public” on Facebook. To report a complaint in your home or community, contact the following agencies:
The Chester County Health Department: 610-344-6225
The Pennsylvania Department of Agriculture: 610-489-1003
The Pennsylvania Agricultural Ombudsman Program: 717-299-5361