Foramsulfuron is commonly used to control perennial ryegrass (Lolium perenne L.) (PR) in overseeded bermudagrass (Cynodon dactylon L.). Control failures observed with foramsulfuron are often associated with cool temperatures. Failure to completely control PR leads to prolonged competition and clumpy ryegrass. Athletic field managers use turf blankets in cool weather to promote growth, improve turf color, and improve spring green-up. We believe that using turf blankets in coordination with foramsulfuron application will increase effectiveness of PR control in cold weather. Studies were conducted in 2006 and 2007 to determine effects of black and white turf blankets on PR control with foramsulfuron.

Trials were initiated in in Blacksburg, VA on bermudagrass overseeded with PR and maintained as an athletic field. Experiments were arranged in a RCBD with 3 replications. Plot size was 1.8 by 1.8 meter. Black and white turf blankets were cut to cover individual plots and were applied one week before, one week after, or one week before and after treatment with foramsulfuron at 29 gai/ha. All cover scenarios were duplicated in the absence of foramsulfuron application for comparison. Also, foramsulfuron-treated non-covered and nontreated non-covered treatments were included for comparison.

One location experienced average maximum and minimum temperatures 1 WAT were 8.3 and -1.7 C, turf blankets do not mitigate cold temperature effects on PR control with foramsulfuron at these temperatures. Average maximum and minimum temperatures at other locations 1 WAT were 21 and 3.5 C. Turf blankets improved PR control at these locations. When blankets were applied 1 WAT, and 1 week before and after treatment, foramsulfuron controlled PR 63 and 80%, respectively, 6 WAT. Turf blankets used after application can mitigate cool temperature effects on PR control with foramsulfuron.