This spring and early summer has been quite weird in the Southeastern US. April and May started off with a real bang considering there was widespread, severe winter injury on bermudagrass fairways, tees and some greens throughout the state. Our winter, especially February, was extremely cold. This February was the fourth coldest on record! I suspect the bermudagrass in shaded areas, north-facing slopes, and poorly drained areas succumbed to cold injury in February. Then as some of the bermudagrass was waking up with some warm March temperatures, a second cold spell hit on March 28 and 29th. Nighttime temperatures dropped to 22oF the evening of March 29th. Basically, bermudagrass received a 1-2 punch that resulted in major winter injury in NC.
We have seen other weird things too, like fairly extensive epidemics of red thread in tall fescue. Although this is not unheard of, it is still pretty rare. We have also seen a fairly substantial outbreak of Ascochyta blight on Kentucky bluegrass and fescues and it appears that it has affected creeping bentgrass tees and putting greens. The substantial rainfall we received in April and early May followed by warm, dry conditions, most likely lead to these unusual diseases popping up.
Another issue we observed on ultradwarf bermudagrass putting greens in April was the lack of protection for Pythium blight. We received numerous samples from throughout the Southeast that were ravished by Pythium blight. I think we only received a single leaf spot sample all spring. From our clinic database it appears that Pythium blight is most prevalent on ultradwarf bermudagrass in March-May (it can occur all year long) and leaf spot is most prevalent in July-October. That being said, the conditions favoring these two diseases are very similar. The symptoms are almost indistinguishable as well; we can only tell the two apart by microscopically examining the structures of the pathogens. The lesson, when spraying for leaf spot mix in a product for Pythium or vice versa.
Everything else is pretty quiet right now. With some timely rains diseases should start to develop soon. We have some interesting trials this summer and I look forward to presenting the results from those!