You Are Here: Management Updates 1999 Archive September 24, 1999

Date: September 24, 1999
Category: Diseases
Subject: Gray Leaf Spot, Red Thread, Rust, Red Leaf Spot, Leptosphaerulina

GRAY LEAF SPOT continues to wreak havoc across New England. I received a sample from a school grounds in Massachusetts in which the ryegrass was severely affected. Surprisingly, the nearby playing fields were not yet showing symptoms. This is the first documented outbreak from UMAss Diagnostic Lab samples outside a golf course. I would be surprised if it is not also affecting ryegrass lawns and athletic fields. The disease develops rapidly and severely, so it should be different from the diseases you are used to.RED THREAD and RUST are active on lawns. Other samples from golf courses this week included some RED LEAF SPOT on a bentgrass green and LEPTOSPHAERULINA LEAF BLIGHT on fairway turf. The latter can be identified by yellowing of mostly the tips of blades and numerous brown fruiting bodies that can be seen easily with a hand lens, especially in wet weather. Most of these problems should clear up pretty well with the advent of drier weather.

- Submitted by: Dr. Gail Schumann