EXTENSION CONNECTION: High rainfall, ice storm bring take-all root rot

Published: Tuesday, May 13, 2014 at 11:00 PM.

Last summer’s heavy rain and stress from January’s icy weather have contributed to widespread take-all root rot.

The culprit? A soil-inhabiting fungus — Gaeumannomyces graminis var. graminis — that causes leaf color loss and yellow grass patches ranging from a few inches to more than 15 feet in diameter.

Symptoms appear in the spring, but the disease can persist all summer and survive winter. Over time, the entire area dies as the root system rots away.

Taking action

When disease occurs, raise the cutting height. Scalping grass damages the growing point; raising cutting height increases the green plant tissue available for photosynthesis, resulting in more energy for turfgrass growth and subsequent disease recovery.

If an area of the lawn has an active fungus, washing or blowing off the mower after use will reduce the disease's spread to unaffected areas.

The amount of water and timing of its application can prevent or contribute to disease development. Most fungal pathogens that cause leaf diseases require free water — rainfall, irrigation, dew — on the leaf to initiate the infection process.

1 2 3

Reader comments posted to this article may be published in our print edition. All rights reserved. This copyrighted material may not be re-published without permission. Links are encouraged.

▲ Return to Top

Local Faves

Tonight in Prime Time