Learning to fly

May 29, 2018 8:17 AM
Blog Post

Tom Petty said he was “learning to fly, but I ain’t got wings.” The last two weeks have made me think about flies way too much. The black flies, sometimes called buffalo gnats, have been terrible and making it hard to be outside. These small flies (1/4" in length) are black or gray and somewhat resemble a small house fly. The thorax is shiny and convex, giving them a humpbacked appearance. The adult females have scissor-like mouthparts and inflict a painful bite to access blood. The bites can cause itching, swelling, and red welts. Some people experience allergic reactions to the bites; however, they are not known to vector diseases to humans.

buffalo gnat
Buffalo gnat. Photo by Darren Blackford, www.ipmimages.org.

Black flies typically appear in late spring/early summer. Males and females feed on plant nectar and females also need blood for egg development. They like to feed on birds and mammals, including humans. Sometimes the fly swarms are so intense they can kill livestock and poultry.

Unfortunately, these flies are highly mobile, very aggressive and difficult to repel. There is limited success with DEET-containing sprays that are normally effective against mosquitos. Wearing long pants and shirts can help while outside. For the next couple weeks, we might have to “learn to fly” indoors as much as possible.


Erin Hodgson Professor

Dr. Erin Hodgson started working in the Department of Entomology, now the Department of Plant Pathology, Entomology, and Microbiology, at Iowa State University in 2009. She is a professor with extension and research responsibilities in corn and soybeans. She has a general background in integrated...