Annual bluegrass control and perennial ryegrass elimination in overseeded bermudagrass with amicarbazone and flucarbazone

摘要

A small plot experiment was conducted at Legend Trail Golf Course in Scottsdale, AZ in a rough area adjacent to a fairway. The Tifway 419 hybrid bermudagrass rough was overseeded with perennial ryegrass cultivar La Quinta during late September 2010. The ryegrass was mowed regularly during the winter at a height of 1.25 in and the bermudagrass was maintained at 1.0 in height. Treatment plots measuring 5 ft by 10 ft were established in a randomized complete block design with three replicates. Herbicideand transition-aid treatments were applied using a backpack sprayer pressurized by C02 at 30 psi and delivering sprays in 47 gpa water. The broadcast spray was applied with a hand-held boom equipped with three 8003 flat fan nozzles spaced 20-in apart. All sprays included a non-ionic surfactant, Latron CS-7 at 0.25% v/v. The first sprays of amicarbazone were initiated on 18 February 2011 when the air temperature was 64°F, cloudy sky, 1 mph wind, dry turfgrass surface, and soil temperature at 4-inch depth was 50°F. P. annua (POANN) was initiating flowering. The sequential applications of amicarbazone were applied three weeks later on 11 March when the air temperature was 71°F, clear sunny sky, wind was 2.5 mph from the southwest, turfgrass had dew, and soil temperature at 4-inch depth was 52°F. P. annua was flowering in 50% of the plots. ARY-0619 at 6.4 oz product/1000 sq ft was added to an amicarbazone 5.0 oz/A treatment at sequential timing of application at 3 weeks after the first application. On 26 May, the transition-aid treatments were applied to eliminate perennial ryegrass (LOLPE) from emerging bermudagrass (CYNDA) when it was 80°F, clear and sunny sky, less than 3 mph wind from the west, and soil temperature was 64°F at 2-3 inch depth. Following treatment applications, P. annua control, ryegrass elimination, and bermudagrass overall quality were evaluated at intervals until transition occurred.