Keep ahead of Pythium

Plan for Pythium blight to prevent onset and damage.


Erin McManus, golf course superintendent at Medina Golf & Country Club in Minnesota, has changed his methods for keeping Pythium blight at bay over the years. He used to rely on fungicides as a control once it showed up. He now uses a combination of planning, cultural practices and other preventive measures to keep ahead of the problem before he starts losing areas of turf.

He pays more attention to weather patterns and forecasts. He was used to Pythium showing up between mid-July and mid-August. The last couple of years it has appeared in late June into early August. Since Pythium likes heat and humidity, especially 2 or 3 days in a row, he watches the forecasts to see when the conditions are predicted to be right. He then starts his preventive program with phosphites ahead of the predicted weather patterns that are favorable for Pythium.

“I used to start that program the first of July, but with this year’s weather patterns, I’m watching the forecasts and will probably start a week or two earlier,” he says. “With the current weather patterns we expect more pressure this year.”

McManus doesn’t worry about Pythium in the rough. When he only sees it there, and no place else, he is even more confident that his program is working.

“The conditions don’t last that long and the grass in the rough doesn’t die back to the extent that there is a lot of bare soil, so we don’t worry about it,” he says.

Cultural practices include keeping the moisture levels down. He says, “I don’t water as much as I used to,” he says.“Even dragging to remove the dew helps mitigate the onset of Pythium. It really helps that players want a firm and dry surface.”

McManus is also well aware of new Pythiums species that have been showing up. He had his first experience last year.

“We had some areas on the greens that we just thought were under stress. Lab tests showed it was P. root dysfunction. So far this year we haven’t seen any sign of it,” he says. “But we now have a better idea of what to watch for.”