You Are Here: Management Updates 1998 Archive June 17, 1998

Date: June 17, 1998
Category: Diseases
Subject: Weather

After all this rain, it might be easier to list the diseases that are NOT active. Fusarium patch/pink snow mold, anthracnose (especially the crown rot stage) and, it appears, the early stage of summer patch. It does not seem possible that summer patch could be active at these cooler temperatures, but it may be the very early stages brought on by the excessive rain. The samples I have seen so far seem to be resulting in slightly yellow patches with the yellow coming from the outer leaves of the plants. The centers and crowns appear to be healthy still which means that curative fungicide applications can be effective. Thiophanate-methyl and Heritage and the two kinds that can be used.

If warm weather quickly follows all the rain, I expect that brown patch will be rampant. Keep in mind that the mycelium of brown patch can look quite white when it is very wet. If it is Rhizoctonia, it should appear in fairly large patches. Pythium blight usually starts in small reddish, greasy pockets and can very much like pink snow mold which remains active in cooler areas.

This weather episode breaks all the "typical symptoms" rules. When there is enough water, almost anything can happen.

- Submitted by: Dr. Gail Schumann