Pythium root rot in March?

We diagnosed a case of Pythium root rot on a creeping bentgrass sample that was submitted to the Turf Diagnostics Lab last week. Really? Pythium root rot in March?

Most people don't start to think about Pythium diseases until June or July, but in reality they can occur at almost any time of year. We routinely see symptoms of Pythium root dysfunction as late as October or as early as February.

Pythium root rot can also occur at any time of year. There are many different species of Pythium that can cause root rot, and while most grow at warm or hot temperatures, some others grow at cooler temperatures. The disease is driven by soil moisture: if the soils are wet for extended periods of time, then Pythium root rot can develop. In the case of the sample that was submitted last week, the symptoms appeared after heavy rainfalls over the prior weekend.

I'm not saying that everyone needs to run out and apply a Pythium fungicide. But if you've had issues with Pythium root rot in the past, and you see more wet weather in the forecast, then it might be a good idea.

For more information about Pythium root rot and its management, refer to the disease profile on Turffiles.