Are You Pythed Off at Pythium Root Rot?
by Halle Hampy, Jim Kerns, and Lee Butler
You have all heard that an ounce of prevention is worth a pound of cure. This is especially true when pathogens attack turfgrasses during the most stressful growing times of the year. For example, when diseases occur in cool-season grasses during the summer months, it can be challenging for the turfgrass plants to grow out of the damage, even when the most efficacious fungicides have been applied. This can be frustrating for growers because they feel like applications were ineffective. Furthermore, we hear stories of growers who have applied multiple fungicides over a few day periods and who are likely confused about which product exactly worked, as they often assume it was the most recently applied product. Based on the research below, it could have been one of the earlier products applied and patience was not a virtue of the grower.
Starting a Pythium root rot program when soil temperatures are consistently above 65F (late April to mid-May) should be sufficient in preventing Pythium root rot. If disease happens to develop, do not expect curative applications to provide immediate suppression of the disease. As with controlling any disease, a lot of recovery is heavily dependent on growing conditions, i.e., Mother Nature. If the weather is favorable for turfgrass growth, fungicides will appear to work faster than when conditions are not favorable. So, get your products out early and you won’t be PYTHED OFF next summer!