Preventative Disease Treatment
Preventative disease treatment is ideal because it reduces headaches down the road. Here are our guidelines for preventative applications to treat dollar spot, Pythium root rot, summer patch, and brown patch.
In April and May, staying ahead of dollar spot is a big concern on bentgrass. Using Xzemplar will help prevent dollar spot. If it has been a problem in the past, make sure your fertility levels are in good shape. Dollar spot is a low-nitrogen disease. Moisture management, like removing dew through early mowing, is also helpful in preventing dollar spot.
Another good broad-spectrum fungicide to prevent dollar spot activity is TMI 2020. It prevents and controls fungal turf diseases on greens, fairways, trees, and other turf sites. With two powerful active ingredients, thiophanate-methyl and iprodione, TMI 2020 offers different modes of action in one convenient product.
Craig Shepherd, an ATS sales representative in the Chicagoland area, explained the importance of preventative applications: “You do not want to wait to spray until a dollar outbreak has occurred. Controlling inoculum is the absolute key to this disease.”
Pythium Root Rot
For preventative Pythium root rot treatment in the transition zone, monitoring the soil temperature is important. You want to start applying fungicides when the soil temperature is at 55–60°F, which is usually late April to early May. Fame +T and Insignia SC are two effective fungicides used to treat those diseases.
Mike Werth, an ATS sales representative in Wisconsin, described the identification of Pythium root rot: “The symptoms first appeared as light green (etiolation-like) patches on a few of my customers’ bentgrass greens. Then, within a few days, the bentgrass declined—and quickly. We immediately took samples to the WTA Diagnostic Turf Lab, and our concerns were verified. It was Pythium root rot.”
Fungicide treatment of summer patch typically involves four applications, 28 days apart, starting when the soil temperature reaches 65°F. Prevention is key when it comes to controlling summer patch, so don’t be afraid to spray even before you see evidence of the disease. Using a combined chemistry approach (DMI + Qol MOA) is often the most successful.
When it comes to preventative spray programs on greens, tees, or fairways, be sure to select the proper spray nozzle and volume of water for uniform coverage. Add Optimizer Green Shade to improve turf color and quality to help manage stresses and moisture.
Brown patch preventative applications should begin in early June through early September when conditions are prime for it to occur. Preventive products that contain FRAC 11 (Strobilurin/QoI) fungicides, such as Zoxy-T, Exteris Stressgard, and Lexicon, are best.