As the weather warms, many suspected pest problems turn out to be drought problems instead. This is not surprising, since the symptoms of drought stress are very similar to the symptoms caused by many turf diseases and insects.
The culprits involved in drought stress range from poor irrigation distribution to localized dry spot to pump failures, to contour issues and/or surface sealing.
Whatever the causes, it is very important to avoid drought stress — for both obvious and not–so–obvious reasons. The immediate damage is of course unsightly. That is the obvious part. But the hidden problem is that because soils that completely dry out are very difficult to re-wet, drought stress can end up being a gift that keeps giving — throughout the summer — as water-repellent soils remain bone–dry, unable to support turf growth and recovery. To alleviate this issue, we apply a soil wetting agent each month from April-September to help provide uniform wetting and moisture penetration.
To detect drought stress before serious damage occurs, we use a hand–held TDR 300 soil moisture probe , outfitted with 4.8 inch rods, from Spectrum Technologies. On sand-based greens, we target 15-25% volumetric water content for healthy turf. I like to irrigate to 35% and let the soil dry down to between 10-15%. This allows the green surface to remain firm yet provide ample moisture for the roots. The data collected is mapped and then we are able to target apply irrigation, making better use of our water resources.
