One of the common comments heard from members and golfers during our late July and early August visits was "summer is just about over, there should not be much to worry about." During these conversations, we always point out that it does not take two or three weeks for problems to occur. With the right weather conditions, rapid turfgrass decline can happen in three or four days. Mind you, there have not been many recent catastrophes, but there has been much more stress on the grass in our recent travels, especially in the areas that received ample rainfall in conjunction with the arrival of high temperatures.

Anthracnose has been more of a problem in recent weeks than it has been in quite some time. Nuisance disease levels have been replaced with noticeable turfgrass thinning in several instances. Summer patch and bacterial wilt have added to problems with Poa annua populations on greens. Make sure that frequent, light applications of nitrogen are made to keep the grass growing and healthy both to resist and recover from these diseases. Spoonfeeding through the sprayer is still a very good way to deliver approximately 1/10 lb. of actual N per 1,000 sq. ft. on a 7-10 day interval. Stress-related diseases generally are worse under low nitrogen fertility.

The other major problem persisting throughout the summer is dollar spot disease, especially in fairways. With budgets tight, efforts to use reduced fungicide rates and extended spray intervals on fairways has led to difficult-to-control dollar spot outbreaks. In each instance where the disease has been a serious problem, nitrogen fertility was low. While excessive nitrogen applications can create turfgrass problems, the grass needs to be fed to keep it healthy.

The other challenge of summer resurgence has been aeration. Many courses scheduled mid-August aeration with the thought that the weather would be breaking at this point in time rather than having the peak of summer temperatures. Be cautious during aeration. At this point in the growing season abrasive dragging or other grooming practices may create problems. Err on the conservative side of maintenance. Use smaller tines, especially if the turfgrass is already weak. Self-inflicted stress can ruin a good growing season.

The weather will break soon enough, but, until that time, be wary of the problems that can still occur during this late summer heat wave. Although it’s been a mild summer, it only takes a few days of summer stress to forget the mild July weather.

The Mid-Atlantic Region agronomists are part of your agronomic support team. If you have a question or concern, give us a call or send an e-mail. Stan Zontek (szontek@usga.org) and Darin Bevard (dbevard@usga.org) at 610/ 558-9066 or Keith Happ (khapp@usga.org) at 412/ 341-5922.