Weather conditions continue to provide management challenges, but we are about halfway through the traditional summer stress period.
The story in this region continues to be the weather! Rain has occurred in some areas, but others are currently under drought conditions. Within a 30 minute drive there has been as much as a 75 percent difference in rainfall amounts since early summer. For some, the rain has been just right, not enough for others, and in rare cases far too much. When this happens in conjunction with high heat, turfgrass decline has occurred. Scald, wet wilt and water mold diseases have been a problem. It is always better to operate from a position of prevention rather than curative treatment strategies when managing pythium outbreaks. Disease pressure has been high and many superintendents have supplemented their treatment programs with conventional fungicides. Research has demonstrated that phosphites may only provide protection from pythium under moderate pressure.
There have been steady outbreaks of Hyperodes weevils this season. Damage has been limited but still there has been a need to scout and spot treat whenever damage is discovered. We are experiencing multiple generations of this insect. It is not uncommon in the same plug to see larvae, pupae and callow adults! Select the controls carefully! One specific product may not control all of the life cycles.
Playing defense has become the strategy of choice this July. The heat has been oppressive and all efforts are being made to minimize any chance of self inflicted damage. Mowing frequency on greens is being reduced and supplemented with rolling. Water is applied carefully, and the grass is being fertilized lightly to promote controlled growth. Playing defense now will make a difference when the weather is more favorable for maximizing playing quality.
Summer weeds, especially sedges, kyllinga and goosegrass have been problematic at many golf courses. Preemergent strategies have been ineffective in many instances. This may be a product of early germination due to warm spring weather. Application timing may have been too late, or pressure may be extremely high. Regardless of the reason for weed emergence, as you consider postemergent strategies, keep the health and quality of desirable grasses at the forefront. A poorly timed herbicide application under environmental stress could severely thin or even kill the turfgrass. While weed populations are unsightly, they are not nearly as unsightly as dead grass. Be sure that weather conditions are right for herbicide applications if they are needed.
Finally, the drought conditions emphasize the importance of monitoring water quality! Water levels are down and this has affected water quality not only for irrigation but also product application. Don’t assume anything. With less rain and greater reliance on wells or even potable water sources, water quality can change. Most public water has pH values in the 7.8 to 8.2 range, which can negatively impact product efficacy. Check the quality of the water to determine if spray tanks need to be buffered to maximize the effectiveness of a treatment strategy. Knowing the water quality will aid in how irrigation is applied, and if deep watering cycles are necessary to flush the profile. Syringing and light watering are being performed frequently. With these applications, salts and other detriments to turf maintenance can accumulate in the upper portion of the soil profile. If these salt levels get too high, turf performance can be affected. Again, know your water quality.
The Mid-Atlantic Region agronomists are part of your agronomic support team. If you have a question or concern, give us a call or send an email. You can reach Stan Zontek (szontek@usga. org) and Darin Bevard (dbevard@usga. org) at 610/ 558-9066 or Keith Happ (khapp@usga. org) at 412/ 341-5922.