PHOTO ©RUSSELL HOLLOWAYI ADOBE STOCK

Heading into Fourth of July weekend, Emilio Polce, president of EcoChoice in Vernon, Conn., called a country club client to check in. “Everything OK?” he asked, reminding the restaurant manager that he’d be off work during the upcoming holiday.

Spilled soda and beer are just one reason why restaurants and bars have small flies as their main pest issue.

That weekend, the client called anyway.

“He is just two miles up the road, so I went there — and I was horrified,” Polce says. “The bar area was not cleaned properly, and there were fruit flies everywhere. They were clinging to the soffit above the bar, and I pointed out the recessed lighting cans and spillage on the flat screen televisions.”

During the conversation, Polce picked up a rag and never stopped wiping. “It was gross,” he says. “I rinsed the rag twice after cleaning the soffit, which took me five minutes.”

The bar manager’s reaction? “His jaw dropped.”

Next, Polce led the manager to a bar seat cushion. He pointed to the crease where the seat meets the back — and it was stuffed with crumbs and dried, sweet liquids from soda and beer. “His jaw dropped again,” he says.

Polce designed a sanitation checklist for the country club’s restaurant/bar — a practice he knows well as a former manager of a Marriott lounge. “Most of the restaurants and bars have small flies as their main issue,” he says.

Regular, thorough clean-ups are critical for managing small flies. Sanitation is the core of effective control.

Polce teaches managers and employees how to properly clean the drains where small flies forage for food. He uses a foamer/mister/sprayer with a built-in compressor. “The foam under pressure goes into the floor drains and pushes up through the P-trap,” he explains. “A lot of times you can’t get under there where the breeding is happening.”

His technicians put a biodegradation product to work on floors and rely on biodrain gels to break down the organic material that flies feed on. In some locations, he’ll install fly lights to control fruit and drain flies that tend to perch on the walls. But ultimately, control is about “simple sanitation,” he says.

Joe Cantu, vice president of operations, The Bug Master, Austin, Texas, uses quick knock-down aerosols to manage flying insects, and drain pucks that insert into a mesh bag that hangs in the drain. “As water enters the drain, it releases material and continues to clean,” he explains.

Most of all, effective control requires changing customers’ behaviors, Cantu says. “Even the best products out there with the longest residual won’t work if the drains remain dirty and there is a buildup of material under kitchen equipment,” he says. “That combats the products and we don’t get as long of a (product) lifespan as we would with proper sanitation.”

UNDERCOVER I.D. Treating small flies requires an investigative eye. “It calls for more inspection — you have to think outside the box,” says Jim Saitman, operations manager, MadCo Pest-a-Side, Wildomar, Calif. He describes a strip mall scenario where stores share plumbing lines. A retailer could end up with a drain fly problem if the plumbing is connected to an adjacent restaurant. “You can throw a scope down the drain and your side is clean — but on the other side, a restaurant is dumping food waste and flies are breeding and coming up through your drain,” he says.

Another scenario: A hospital account had a pervasive small fly problem that felt out of control. “After doing everything possible, the drain pipes were cracked and there was a cavity under the building,” Saitman says.

Eight million dollars later, the three- story hospital was excavated and lifted 4 feet up to address the cracked pipe, rerun the drains, remove the soil and bring in new, clean soil. “It was either that or shut down,” Saitman says.

Kevin Lemasters confronted a similar issue at a hospital account. “Phorid flies kept showing up and we didn’t notice any drains close to that room,” says the associate certified entomologist and president of EnviroPest in Colorado.

After about six months of trying every treatment possible, Lemasters says the team discovered a cracked pipe under the flooring. “Once they opened up the floor and corrected the pipe issue and got rid of the moisture in the soil, the problem went away,” he says. “We suspected that and talked about it, but we weren’t quite looking in the right places to get it figured out at first.”

Phorid flies are often misidentified, points out Josh Fleenor, president, Pest Pros Pest Solutions, Sacramento, Calif. “People focus so much on fruit flies when they can really save headaches by properly identifying the pest,” he says. “I can’t tell you how many accounts I’ve been called into and they’ve had three other companies out there, and we’ll scope their plumbing lines and identify a crack that is dripping into a subsurface area, creating a pocket where phorid flies thrive and come up to the surface a few at a time. If you don’t identify that, you’ll go nuts trying to control the flies with materials.”

EFFECTIVE TREATMENT. Pest Pros focuses its small fly control on addressing larvae. “We’ll knock down adults with a standard material by getting a bio-gel product into the drains and removing grime,” Fleenor says.

He believes that insect growth regulators (IGRs) are underutilized in the small fly sector. “These have a more proactive, long-term approach to control as opposed to just dealing with what’s right there,” Fleenor says. “A lot of technicians see a small fly, kill the small fly and think the small fly problem is solved, but it goes deeper than that.”

By using IGRs in cracks and crevices close to target areas by decaying organic matter, Fleenor says larvae development is restricted so the flies cannot lay eggs again. “If we can put a huge dent in the egg population, we are going to put a massive dent in the adult population,” he says.

PMPs have a wide range of tools in their toolbox for small flies. Fleenor explains that bio-gels are effective because when scrubbed into a drain with a pipe brush, “It will break up debris on the inner rip of the piping,” he says. Foaming materials penetrate drains more deeply and address fermenting material where small flies lay eggs and develop into larvae — before they mature and eventually fly out of the drain.

Jeffery Preece turns to microbes for restaurant and bar accounts. Sanitizers, on the other hand, only clean the surface. “We have to address the [sludge] that small flies breed in,” says the technical director of ZipZap Termite & Pest Control in Pleasant Valley, Mo.

And when that happens effectively, the company can reduce or eliminate callbacks. Preece says, “If we communicate what needs to be done to prevent small flies, we typically do not have callbacks because customers understand the problem.”