With the recent drop in temperatures and snow beginning to accumulate in northern areas, many courses have already made their final plant protectant application to putting greens – or will do so soon. This final application typically targets snow mold, but there is also an opportunity to target other issues. Research and field observations suggest that getting a jump-start on controlling Poa annua seedheads now can pay dividends down the road.
Traditional seedhead suppression programs typically include ethephon and trinexepac-ethyl applications in spring. This program calls for tank-mixing the products and making the first application at 400 growing degree days (GDD) with a base temperature of 32 F, or at 50 GDD with a base temperature of 50 F. A second application would follow three to four weeks later. However, making an application of ethephon to the turf when it is dormant has been shown to help improve upon the traditional seedhead suppression program.
Adding ethephon at a rate of 5 ounces per 1,000 square feet to the final fungicide application of the year, when turf growth has ceased, can improve seedhead suppression when followed up with the traditional program outlined above.
This additional application is not a surefire method for complete seedhead suppression, but it does offer a safe opportunity to improve upon traditional methods. To discuss seedhead suppression or snow mold control programs in greater detail, contact your regional USGA agronomist.
Northeast Region Agronomists:
Adam Moeller, director, Green Section Education – amoeller@usga.org
Elliott Dowling, agronomist – edowling@usga.org
Paul Jacobs, agronomist – pjacobs@usga.org
Information on the USGA’s Course Consulting Service