Written by Paul Blessing - Turf & Horticulture Manager
Dollar Spot in Bermuda Turf is beginning to pop up on several customer sites. It appears as small spots approximately the size of a dollar coin, hence the name. These spots can expand up to 6” or more in diameter in severe conditions. The infected leaves typically remain upright, and have white-to-tan lesion on the leaf blade. These lesions start out with an hourglass shape in the middle of the leaf with reddish brown margins. As the lesion expands it girdles the leaf blade which causes the top part of the leaf to turn completely brown.
Dollar spot fungus begins to grow when nighttime temperatures exceed 50 degrees, even though the disease symptoms may not appear until later in the spring. This disease also needs 10-12 hours of free water to sit on the leaves at night which occurs either through heavy dews or extended periods of wet, overcast weather. Dollar spot remains active throughout the summer, but disease activity generally will stop once daytime temperatures exceed 90 degrees.
Typically, fungicides are not necessary. Nitrogen fertilizer will allow the Bermuda turf to outgrow the disease, and prevent further development. Drought stress and excessive or evening watering will encourage dollar spot. It is important to maintain a proper water regiment. Water between the hours of 30 mins before sunrise up to 10:00 am. Water deeply less often to promote a stronger root system. To do this apply 1/2 inch of water. To determine how long to water ½ inch, place 2-3 tuna cans in the watering area and water for 15-20 minutes. Measure how much water was collected and adjust your time to achieve the ½ inch.
If you would like more information on Turf Management, please reach out to your local GreenView Partners representative.