You Are Here: Management Updates 2000 Archive July 24, 2000

Date: July 24, 2000
Category: Diseases
Subject: Bacterial Wilt, Black Layer, Leaf Spot, Dollar Spot, Red Thread

ANTHRACNOSE continued to dominate the golf course disease scene. Most cases, luckily, were the foliar stage which responds better to fungicide compared to the crown/basal rot stage. Other practices to speed recovery include: temporarily raising the mowing height, adding a little nitrogen, avoiding sand topdressing (which abrades plants), rotating traffic patterns and cup placement. Another case of BACTERIAL WILT was diagnosed on very wet, compacted greens. BLACK LAYER was noted in some compacted greens following the rainy weather.

In both lawns, grounds, and golf courses, leaf blighting from leaf spot fungi such as DRECHSLERA, CURVULARIA, and LEPTOSPHAERULINA were common. Unlike spring leaf spots that are distinctly visible, mid-summer leaf blighting often follows drought or heat stress and causes a more generalized yellowing of the leaf. Leptosphaerulina produces numerous dark brown fruiting bodies which are usually visible by eye, especially in moist conditions. In most cases, cultural practices, i.e. stress reduction, can reduce the effects of these diseases. DOLLAR SPOT is becoming very active in some areas, but RED THREAD seems to have nearly disappeared in most areas.

- Submitted by: Dr. Gail Schumann