This spring has been one of the coolest and cloudiest on record. Just last week I was in Stevens Point, WI and soil temperatures barely reached 60 F. Still prime time for take-all patch and fairy ring preventative applications. To be honest not much is happening around the Upper Midwest. We have had reports of brown ring patch, but thats about it. Derek Settle at the CDGA has reported brown ring patch and a bit of dollar spot. We have seen and heard of multiple cases of creeping bentgrass turning red this spring. We think it is a combination of proxy/primo or trimmit + DMI fungicides for take-all/fairy ring + cool temperatures. The symptoms are typically seen on older leaves and we cannot find spores of any kind in the samples. An image of the symptoms we are seeing is above, sorry the image does not show the symptoms very well. If anyone has any thoughts on this matter they would be welcomed and appreciated!
Finally I thought I would reiterate a former post Lane wrote. He presented a succinct description of diseases that typically affect creeping bentgrass and annual bluegrass putting greens. There has been concern in the Midwest with the substantial amounts of rainfall we have received that Pythium root rot could be a problem. Yes Pythium root rot could occur at anytime as long as the soils are saturated, but considering creeping bentgrass and annual bluegrass grow well during the spring I rarely think of Pythium root rot as an issue. This brings me to another point Lane made in a previous post, is Pythium root rot a disease. I think it is a disease because we would not see symptoms characteristic of root rot if the pathogens were not present. Keep in mind though once/if summer rolls in and we continue to receive significant rainfall, then we might see issues with this disease. I am not saying that fungicides are not warranted, but I do think it is unlikely that Pythium root rot would/did occur this spring in the Midwest.