You Are Here: Management Updates 2001 Archive July 25, 2001

Date: July 25, 2001
Category: Diseases
Subject: Summer Patch, Brown Patch, Pythium, Gray Leaf Spot

SUMMER PATCH has been diagnosed on golf courses in the area. This is a stress-related, root disease of annual bluegrass. Curative control is best using azoxystrobin, watered-in, but keep in mind that badly infected plants may not recover. The long term solutions area to prevent stress (compaction, excessive thatch, insufficient water) and/or replace the Poa with bentgrass. DROUGHT symptoms unrelated to any obvious fungal pathogens have also been observed. Many lawns are going dormant, but drought problems are also common on golf courses where irrigation systems do not deliver uniform water. Symptoms are most common where roots are shallow and thatch is thick. Even the best irrigation systems have trouble replacing a good, soaking rain which has not occurred in most areas for a while now. The good news is that the next few days will be cooler. When nights dip into the 50s, both BROWN PATCH and PYTHIUM BLIGHT will no longer be active, so you can probably save yourself a fungicide spray tomorrow. Watch perennial ryegrass areas for GRAY LEAF SPOT. It has not been confirmed in New England yet this season, but could develop rapidly if we get some rain.

- Submitted by: Dr. Gail Schumann