The bermudagrass stem maggot, a pest found in parts of Georgia, Louisiana and Tennessee, is also showing up in Florida hayfields, according to University of Florida entomologist Russ Mizell.

The invasive fly species, native to Hawaii, Japan, Indonesia and India, first appeared in the continental U.S. in 2010. Its flies infest bermudagrass fields, retarding growth that reduces forage quantity as well as quality, he notes. When they should be green, fields or pastures infested by the maggot look frosted brown in the middle of summer.

Maggot larvae can be detected by splitting grass stems from the tip to the first node, according to Mizell. Mature larvae eventually leave stems, enter soil and emerge as adult flies in a week to 10 days.

Thicker-stemmed varieties of bermudagrass are less affected by stem maggot damage than thin-stemmed varieties, notes University of Georgia Extension forage specialist Dennis Hancock.

Producers have had some success deterring the pest by using two applications of pyrethroid insecticides. However, because the flies move easily among fields, this method of control isn’t always effective, Hancock says.

For more on the pest, read our story, “Bermudagrass Stem Maggot Is Here To Stay.”