Because of its aggressive growth, especially during cool weather, perennial ryegrass has to be mowed often. The incorporation of the plant-growth regulator trinexapac-ethyl (available commercially as Primo) into the cultural program provides some mowing relief and is believed to enhance summer root growth and quality. The fertilization program is conducted to ensure that essential nutrients are provided in sufficient quantities to sustain healthy growth, while minimizing clipping production and pollution potential. Intensive hollow-tine cultivation is per- formed to control soil compaction and provide a planting bed for the new crop of perennial ryegrass established each year, immediately following the Labor Day tournament. Chlorpyrifos (available commercially as Dursban) was used for insect pest control when needed. Dithiopyr (available commercially as Dimension) is applied in early spring for preemergence control of annual weeds.