Poa seeding has proven to be worse this spring than years past on the North Course. Although it is undesirable on all surfaces, greens are affected most especially in quality of ball roll. The North greens are a mix of two grass varieties bentgrass and Poa annua. Because of low cutting heights, bentgrass does not produce seed. Unfortunately, even at low cutting heights Poa does produce seed. Normally this occurs for 4 to 6 weeks but can be prolonged by cold weather. During this time the Poa plants become very dense and puffy compared to the bent and they also attempt to push there seed heads upward which makes the surfaces inconsistent and “bumpy”.
Our main weapons against the seed heads is the use of chemical plant growth regulators which inhibit the seeding hormones of the plant. We apply on an interval of every 2 weeks on the North Course “low cut surfaces” and maintain about 75% to 90% control. Daily mowing and “vertical mowing” also assist in harvesting some of the seed heads that are produced. As the summer starts up, seed head production will stop and surfaces will become more uniform.