UNIVERSITY PARK, Pa. -- Nothing inspires more disgust than the sight of a cockroach crawling across your floor, but an entomologist in Penn State's College of Agricultural Sciences says homeowners often inadvertently invite these critters into their homes.

"German cockroaches, which are the most common type of cockroach found indoors in Pennsylvania, do not travel outside of structures," says Glenn Holbrook, assistant professor of entomology. "Homeowners often bring cockroaches into their homes in containers from infested warehouses, stores or other homes."

Holbrook says the nymph stage cockroach is quite small and can be transported into homes in paper bags and particularly cardboard boxes. Cockroach nymphs often settle in the corrugated passageways in cardboard containers.

"Roaches love to live in small places where they can feel surrounding walls over their entire body, so cardboard is perfect for them," Holbrook says. "The best bet is to leave any boxes from stores or from friends outside."

Holbrook says roaches can hide in any kind of box, regardless of its contents. "They can hide in an electronics box as well as in a box containing food," he says. "Many warehouses and warehouse-style retail stores store food containers and other merchandise together."

Once cockroaches are in your house, Holbrook says there are several likely places to look for them.

--Kitchens. The availability of food makes this the first place to look for cockroaches. "Cockroaches don't need much -- after all, they're scavengers," Holbrook says.

--Bedrooms. If homeowners like to eat in bed or keep glasses of water at the bedside, these habits might attract roaches.

--Pet areas. Holbrook says the most often overlooked food source for cockroaches is pet food. He recommends feeding the pet once, cleaning out the food dish every day and never leaving pet food out overnight. "We raise research cockroaches in our labs and do you know what we feed them?" he says. "Dog food. They love it."

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EDITORS: Glenn Holbrook can be reached at 814-865-2435.

Contacts:

Chuck Gill cdg5@psu.edu 814-863-2713 814-865-1068 fax