USGA August Update

The Magic August 15 Date Is Here

By Jim Skorulski, senior agronomist, Northeast Region
August 15, 2012

The magic August 15^th date for Northeast golf courses is here, at least on paper. The days are shorter and that is a plus. It still feels pretty darn warm and humid though. It has been a long year. While it has not been as hard as some, it has been relentless. August aeration dates are fast approaching for some. It is important to use caution with this practice, especially if your annual bluegrass greens are weak. The stress from the aeration process combined with warm, dry conditions may be too much for the shallow-rooted turf to tolerate. Overseeding damaged areas should be done with care as well, particularly if the golf course remains busy. It might be best to begin some less invasive dimple or spike seeding and wait with the more aggressive tactics for a week or two longer when weather conditions are more likely to be favorable and the tee sheets open up.

The long and hot summer has brought with it more crabgrass and nutsedge than I have seen in some time. Crabgrass is having its way in non-treated rough areas and is now even making a strong presence where early spring applications of preemergent herbicides were used. Early applications of dithopyr or pendimethalin are just not holding up with the extended period of heat we have experienced. Even split half-rate applications made on traditional early spring dates are showing break through at some golf courses. The second half-rate application applied in late May or June was just not enough to hold the crabgrass back. Prodiamine, with its longer residual, seems to be holding up slightly better. The lesson learned this season is to try wait as long as possible before applying the preemergent materials. Sprayable formulations of dithopyr provide post emergent activity against young crabgrass plants so the application can be made later. Fortunately, herbicides like Acclaim Extra® and Drive® do offer opportunities to treat the crabgrass. Drive® applications are underway at many golf courses in hopes of controlling the weed before it drops its seed.

The advent of the TDR moisture meters is one of those occurrences that have a profound impact on golf course management. The benefits of that tool are most apparent in a season such as this. If you do not yet have one you are missing out on a tool that will improve your water management capabilities and make you a better turf manger. The sensors offer a quick and accurate measurement that can be used to guide water applications or monitor moisture retention. I have heard experienced superintendents more than once this year say that they have changed their minds about this tool. Although it is certainly possible to evaluate soil moisture with the traditional method of probing the soil the manual process is slower, more difficult and not nearly as precise. Make a TDR meter a must buy for 2013.

We are close to turning the corner with the summer weather, or so we hope. The annual bluegrass has performed pretty well for the most part, but it is “tired.” Superintendents and staffs are tired too. This is not time to shoot yourself in the foot with a hasty decision you may regret long into fall. Hold it together. Football season is just about here. The pumpkins are ripening at Sully’s vegetable stand which a sure sign that we have just about made it.

Northeast Region Green Section - Dave Oatis, director doatis@usga.org; Adam Moeller, agronomist amoeller@usga.org:Jim Skorulski, senior agronomist jskorulski@usga.org.