Susceptibility of Annual Bluegrass and Turfgrasses to Bensulide and Three Uracil Herbicides

Abstract

Golf putting greens were sprayed with N-(2-mercaptoethyl) benzenesulfonamide S-(O,O-diisopropyl phosphorodithioate) (bensulide). Creeping bentgrass (Agrostis palustris Huds.) and annual bluegrass (Poa annua L.) were observed for injury. Preemergence and postemergence treatments of 5-bromo-3-sec-butyl-6-methyluracil (bromacil), 5-chloro-3-tert-butyl-6-methyluracil (terbacil), and 5-bromo-3-tert-butyl-6-methyluracil (hereinafter referred to as DP 733) were applied to a prepared seedbed planted with Kentucky bluegrasses (Poa pratensis L., var. Merion and var. Newport) and annual bluegrass.Thirty lb/A of bensulide produced leaf discoloration and root length reduction of established annual bluegrass plants without injuring creeping bentgrass. Terbacil at 0.2 lb/A and bromacil at 0.4 lb/A gave highly selective control of annual bluegrass in Merion and Newport Kentucky bluegrasses when applied preemergence to the three grasses. Postemergence applications of these compounds produced moderate selective control of annual bluegrass.

Effectiveness of Bensulide in Controlling Two Annual Bluegrass (Poa annua) Subspecies

“…Some report excellent control of annual bluegrass with all of the PRE herbicides in their studies (6,7,11,15,17,18). Others report poor or erratic success with many of the same herbicides, rates, and method of application (2,7,12,14,24,25,29,33). In many of these studies bensulide was reported to control annual bluegrass very well (5,10,13,15,17,18,23,26,30,37), and in many of the same studies bensulide caused little or no injury to bentgrass (9,10,26,29,30).…”

“…Others report poor or erratic success with many of the same herbicides, rates, and method of application (2,7,12,14,24,25,29,33). In many of these studies bensulide was reported to control annual bluegrass very well (5,10,13,15,17,18,23,26,30,37), and in many of the same studies bensulide caused little or no injury to bentgrass (9,10,26,29,30). However in these studies workers did not distinguish which subspecies of annual bluegrass was involved.…”

Phytotoxicity of Herbicides to a Penncross Bentgrass Green

“…However, residual effects of DCPA on uniformity were slight; and little residual effect occurred from a single application. Neidlinger et al (4) reported that bensulide at 16.8 and 33.6 kg/ha did not cause visible injury to creeping bentgrass and colonial bentgrass (Agros tis tenuis Sibth) greens.…”

Annual Bluegrass Control in Overseeded Bermudagrass Putting Green Turf1

“…Herbicides normally used for preemergence crabgrass control in turf were reported to reduce the stand (2,3,5,7) and clipping weights of annual bluegrass (6). Bensulide (0,0-diisopropyl phosphorodithioate Sester with N-(2-mercaptoethyl)benzenesulfonamide) and DCPA (dimethyl tetrachloroterephthalate) gave control of annual bluegrass seeded immediately prior to treatment; however, when seeded at two months after treatment, no effect was noted.…”