I have been on a slight Turf Disease Blog hiatus, and I apologize for the lack of posts recently from my region of the US. In Texas, we have been celebrating the fact that basically the entire state now is drought free. The heavy rainfall events we experienced earlier in the year have finally started to dwindle somewhat. We have been going through a much drier spell here in Lubbock, but there are chances of rain coming up shortly.
I follow many different agronomic pathologist from around the country on twitter, and there has been a lot of discussion about stripe rust showing up in different areas. The wet conditions followed by some drier conditions must have created a great environment for rust to form on our cool-season grasses in this region. The superintendent at a golf course in Amarillo, TX sent me a picture of some struggling turf they noticed on May 28, 2015 (Image 1). This picture was taken of Kentucky bluegrass. If you can look closely at the picture, the leaves are covered in urediniospores.
Additionally, about one month ago, I noticed the tall fescue in my front yard started looking a little off color and brown. There was still plenty of moisture in the soil, so I did not think it could have been drought stress. After taking a closer look, the leaves were covered with urediniospores and becoming chlorotic to necrotic. I immediately watered the area really good to wash the spores off of the leaves, but there are still many symptoms still present on the tall fescue at my house (Images 2 and 3). The tall fescue portions of our research farm are also highly infected with the rust fungi as well. Although the quality is reduced, I am not overly concerned about controlling the rust.
I mostly found this interesting because I do not remember ever seeing rust be a big problem in the past here or on these cool-season grasses in general. We would always get heavy infestations of rust on perennial ryegrass overseeded into bermudagrass when I was at Mississippi State each year. It is highly possible that the environmental conditions were just favorable for pathogen development with the heavy rains followed by dry conditions. If you are growing any cool-season grasses in this region, you may want to be on the lookout for rust at your location.