Golfdom, April 2015

Super Science Color me interested Turf colorants for aesthetics and or as an alternative to overseeding By Grady Miller Ph D and Drew Pinnix MS T urf managers in the southern United States have traditionally overseeded warm season turfgrasses during the fall in order to maintain aesthetically pleasing playing surfaces as well as playability throughout the period of dormancy Te most significant negative attributes to overseeding are the agronomic and aesthetic challenges of transitioning the playing surface from a cool season grass back to a warm season grass while experiencing temperatures that are prone to wide fuctuations Overseeding is not the only way of having green turf during the winter months of the year In recent years turf colorants have served as the standard for an alternative to overseeding warmseason grasses and as a result a number of new products have been introduced to the market Te increase in popularity particularly on golf courses can partly be attributed to the spring transition from overseeded grasses to bermudagrass which has become more problematic due to heat and droughtresistant Applied to semi dormant turfgrass the color will look better For optimum results dont wait until the turfgrass is straw brown cool season grass varieties Conversely prolonged cool springs similar to what we have experienced here in the Southeast the previous two years have also allowed overseeded grasses to persist through May and June causing delays in bermudagrass green up The use of turf colorants Research provided and funded by USGA allows for a much more predictable spring green up and contributes to a healthier stand of bermudagrass going into the summer In order to better understand how a number of these new products visually perform and persist over time a product evaluation study was initiated at the North Carolina State University Turfgrass research facility in Raleigh N C in November of 2011 and 2012 Results oveR the YeaRs We have conducted numerous studies at North Carolina State University to evaluate various colorant products Our first detai led studies were applied to putting greens in fall 2008 Subsequent trials have included evaluations on bermudagrass and zoysiagrass at an assortment of mowing heights In total we have evaluated more than 30 products These include products from manufacturers distributers such as BASF Burnett Athletics D Ervasti Sales Enviroseal Geoponics Harrells J C Whitlam Manufacturing John Deere Landscapes Milliken Missouri Turf Colorant Pioneer Athletics Poulenger USA Precision Laboratories Solarfast US Specialty Coatings and World Class Athletic Surfaces In the earlier studies we applied colorant treatments to completely dormant turfgrass in late October to early November using a boom sprayer and f lat fan nozzles at rates ranging from 40 to 160 gallons per acre gpa Applied to bermudagrass colorant increased turf color from 38 percent to 67 percent relative to the control at the time of painting Of course there was some variation in how the color was judged over time But remember the saying beauty is in the eye of the beholder Most of these products will have a date in which they will need to be re applied to get season long green color Over the six years we have tested these products some years the color lasted the full winter and some years it did not On average the best products will have good color for about 75 days Products were found to be rate responsive Applying the colorants and water carrier at 160 gpa provided turf color increases up to 44 percent greater than the 80 gpa treatments Applying colorants at rates above 80 gpa also resulted in increased color longevity over the winter season As a general rule as turfgrass height of cut increases rate of colorant application will also need to increase Our studies have also shown that when products were applied to semi dormant turfgrass the products performed much better due to the greater background color at the time of application Tis is a very important point Some background color goes a 34 Golfdom April 2015 Golfdom com