Several PGR's, like Primo, TGR and Cutless are becoming popular maintenance tools for intensively managed turfgrass areas such as golf courses. PGR's are used on golf courses to decrease turfgrass height and, consequently, mowing frequency and to enhance turf color. Although many researchers have studied PGR effects on turf growth and color, little information has been published about their influences on turf weeds.
Weeds exist in all horticultural amenities including intensively maintained turfgrass areas.
Weeds compete with turfgrass, for available growth factors and weeds can gain a competitive advantage when turf is not actively growing. PGR's significantly decrease turfgrass growth but the effects of these chemical on most turf weeds are unknown. Weeds may be allowed to further exploit the surrounding areas if PGR's inhibit turfgrass growth more than weed growth. The weeds used were common bahiagrass, purple nutsedge, goosegrass and large crabgrass. Tifway II bermudagrass was included for comparison.