The Ohio State University

Home TurfNotes Poa annua has taken a real hit this past week. The Poa annua decline we have observed looks similar to dollar spot, pythium, insect damage, etc. Most samples I have received do NOT have disease. Although there is a fair amount of disease out there such as dollar spot, brown patch, Pythium on lush/wet or juvenile turfgrass, summer patch, take-all patch, leaf spots, and rust were all reported. Wet conditions with heat can be a death trap. Many areas had excessive rainfall several weeks ago and now are still wet or drying out and experiencing high temperatures.

Monitor watering carefully and address drainage issues. Get air to the roots and be conservative with maintenance. The first two symptoms show Poa annua decline due to water saturated soil condition in combination with the high temperatures we had this past week. In some instances the water saturated soils developed a black layer (bottom photograph). The third picture from the top shows Poa decline that looks similar to dollar spot. Note the creeping bentgrass in the background is not showing decline.

Additionally, some yellowing of Poa annua from high rates of sterol inhibitor / DMI fungicides... be careful!

Posted by Joseph Rimelspach