Now that we are on the cusp of October, and fall seems to be definitely in swing,I think it is a good time to stop and reflect on your summer program and ask yourself what worked and what didn't. It was another stressful summer, and taking a few minutes now to think about what you would like to change for next year will put you ahead of the competition down the street.

The first thing I do when looking back over my summer fungicide programs is try to determine one or two things that really seemed to work. This year in our programs trial one of the clear winners was the importance of appropriate fertility. We compared two programs that featured {Foliar} fertility products. One program used 0.25 lbs N/1000 sq. ft. per month while the other program used twice that amount. What did we find? The program using 0.5 lbs N/1000 sq. ft. per month had significantly better turf quality and color throughout the entire season. It also happened to have numerically less disease than its N reduced partner program. Another winner was a fungicide program that my graduate student and I developed with the artificial constraint that the program had to cost less than $4500 for 3 acres of bentgrass for 7 applications during the summer. I will share more about the specifics of the program in another column, but the key thing I learned from this program was how important it was to use DMI and strobilurin fungicides early in the summer. In this program we had those two important modes of action going down in the first application at the beginning of June, and it set the program on a course to have one of the best turf quality ratings throughout the season. This program also was in the category of having the least amount of disease throughout the season. So proper fertility and DMI and strobilurin applications early in the season are both steps in the right direction, now let's consider what we would change.

Every fungicide program has weaknesses. It is important to remember that when a fungicide program is designed, it generally focuses on the major issues that particular species of grass faces, and tries to control them. It doesn't cover everything under the sun. For example, this year in our trial we had a significant amount of anthracnose. This is not generally a disease that you think about needing season long control in bentgrass. Predictably, only a few programs provided control of this disease. Most programs were not designed to control anthracnose because it generally is not a major problem on bentgrass. Another glaring weakness in most fungicide programs is the lack of sufficient Pythium control applications. The reason for this is that weather conditions conducive for Pythium blight just don't happen all season long. That's why it is good to have those options on hand so that if you see weather forecasts suggesting conditions might be conducive for disease, then you can go ahead and make an application for protection. Minimize the weaknesses wherever possible. Given the lack of anthracnose control, one could make a curative application if the disease was observed, or evaluate what fungicides might be changed that would control anthracnose in addition to everything else. For the Pythium blight issue, my recommendation would be to watch weather forecasts and add those fungicides to the application when conditions warrant their addition. Weaknesses are inevitable, there aren't any "bulletproof" programs, the key question is what you will do to minimize them. Next, lets discuss the environmental conditions that make it more difficult to produce quality bentgrass in the summer.

When nighttime temperatures climb into the upper 70's or low 80's bentgrass begins a major decline in quality. It is just difficult physiologically for this species to perform under those kinds of conditions. Can you do anything to alleviate Mother Nature's impact? Absolutely. First, and foremost is to properly manage water in the rootzone. Several superintendents have begun using soil moisture probes to monitor what the soil moisture is in a rootzone. Most superintendents can tell when they get too dry - plants start to wilt. However, my biggest concern is telling the difference between adequate moisture, and too much moisture. This is where the soil moisture probe has a distinct advantage over other methods as it helps maintain soil moisture in a range where there is enough water for plant use, but also plenty of oxygen for root health. Air movement is another area that will help with environmental conditions. Fans are often better than fungicide applications in helping bentgrass under heat stress conditions. Moving air helps maintain water movement in the plant and allows it to continue to keep itself cool. Coupling fans and light syringing can also have a tremendous impact on surface temperatures and allow plants just enough breathing room to make it through the stressful afternoon. Finally, using products that contain plant stress products (e.g. Signature, etc) can help reduce the impact of those stressful conditions. Phosphite products have been shown to produce compounds in the plant that reduce plant stress. Couple that with some of the formulations that contain compounds that filter and reduce the damaging effects of UV light (e.g. Signature) and the result is a plant better able to handle the stressful environmental conditions that it faces during the summer. When you think about what to do next year, consider how you will manage abiotic stress too.

It is October. Early order is around the corner, and next summer is only 7 months away. Spend a few moments now when everything is fresh and review your program. Ask what worked, what didn't, and how you're going to manage the abiotic stress. Coupling as many of these practices as possible into your management scheme will allow you to maintain high-quality bentgrass under challenging conditions, and will hopefully put off those questions about when you're switching to ultradwarf bermuda.

Dr. Brandon Horvath is a column writer for Landscape Supply, Inc.'s LSI Connections, a newsletter that is sent to our partners in business once per month. Dr. Horvath is a professor and a plant pathologist for The University of Tennessee Turf Program.