Pythium root rot became a turf maintenance concern about four years after the opening of Lincolndale, N.Y.’s Anglebrook Golf Club in 1997.
The course has greens made to USGA construction standards, using an 80 percent sand, 20 percent peat profile. As the greens matured, superintendent Louis Quick noticed one spring that the putting surfaces were not greening up and were not responding to fertility.
“We sent a sample off for testing and it came back with high Pythium counts,” Quick recalls. “Pythium root rot is always in the environment. It just needs opportunity to become a problem. From that point on we have used a Pythium fungicide every spring as soon as we can get on the greens to spray.”
Quick says this past winter’s weather may have an effect on the severity of rot root.
“Pythium can, like most fungi, be opportunistic to a weak plant. But, we are looking good this spring. Most likely because we sprayed a Pythium fungicide as one of the last sprays on the greens and tees.” The timing of this application, Quick says, is usually late October or early November in his area of New York State. “To keep Pythium root rot under control we are spraying a fungicide, first and last, on greens and tees.”
Fortunately, Quick says, Pythium blight has not been a problem at Anglebrook, although there have been a few isolated occurrences in the rough areas of the course. Pythium blight commonly occurs with hot moist conditions that extend for more than one day.
“The blight that I have seen is usually in areas that have standing water or areas that stay wet for extended periods of time,” he says. “Pythium blight needs that water to thrive and uses running water to move and infect more areas. With extended periods of high heat and humidity, I have seen small infections of Pythium blight. High heat means above 90 degrees Fahrenheit, which does not happen that often where we are at in New York.”
Quick treats preventively for Pythium blight when conditions favorable for its development are noticed, usually only a couple of weeks during in the heat of the summer. Root rot is also treated preventively with early spring and late fall applications.
“We use a rotation of fungicides for these applications,” he says. “Signature and Banol are my two most commonly used fungicides for Pythium. I have used them in a tank mix together and separate. I have also used Subdue and Koban to change the chemistry. I also like to have some granular product on hand for emergency application on Pythium blight. Granular Subdue can be put out pretty quickly to stop blight from progressing.”
The most recent addition to Quick’s arsenal of weapons used for Pythium control and overall turf root health is the use of a phosphite product. “You can tank spray these as part of your program or like we do here inject the product into the irrigation system. Since putting the phosphite into the program we have seen an improvement in turf quality, especially in the summer stress periods.”
Because Pythium can be very damaging to turf, it is not a disease Quick waits to scout out before treatment. “It is more expensive to treat preventatively, but with our history of root rot it is a necessity.”