Bermudagrass stem maggots were discovered damaging bermudagrass pastures and hayfields in Georgia for the first time last summer, reports William Hudson, University of Georgia Extension entomologist.

“This is the first record of this species in North America and may represent a new serious pest of bermudagrass forage crops and turf,” says Hudson.

Bermudagrass is the most widely grown grass for forage, pasture and hay production in the Coastal Plain region of the southeastern U.S. It’s also widely used as a turf crop, representing the bulk of sod grown in Georgia, where its value was put at $116 million in 2009.

Last July, extensive damage to bermudagrass pastures was reported by county agents in southern Georgia.

“The damage consisted of the death of top leaves and growing point of infested stems in a manner that had not been observed before,” says Hudson. “Many fields were heavily infested and gave the appearance of frost or cold damage. The damage was quickly associated with very small stem-boring maggots.”

Small gray-and-brown adult flies were collected and later identified as a Atherigona reversura, a species native to Asia. In August and September, entomologists concluded that the pest is present throughout southern Georgia, northern Florida and parts of Alabama and South Carolina.

“Several on-farm trials with registered insecticides found that a single application only reduced infestations for a short time,” says Hudson. “University of Georgia entomologists also observed a noticeable difference in damage levels among bermudagrass varieties. Ongoing laboratory and field research studies next season will examine the biology and methods of control of this new bermudagrass pest.”