SportsTurf provides current, practical and technical content on issues relevant to sports turf managers, including facilities managers. Most readers are athletic field managers from the professional level through parks and recreation, universities.
Issue link: https://read.dmtmag.com/i/77829
FieldScience manager is forced to switch to an alterna- tive topdressing material it is essential to select a material with the same or lower proportions of fine material; fine sand (0.1 to 0.25 mm), very fine sand, silt and clay. Placing material containing a greater amount of fines over your existing sand will result in poor space discontinuity, which will decrease surface infiltration rates and produce a perched water table affect. COST-EFFECTIVE CRUMB RUBBER USE >> Above: IF CORE CULTIVATION DEPTH penetrates the topdressing layer, or sand-cap (top photo), these cores should be removed to prevent drainage from being compro- mised by the native soil that is brought to the surface. tially more expensive than sand topdress- ing ($1,000 per 1,000 kg) has been shown to significantly improve turfgrass wear tol- erance in extremely high foot traffic areas, when sand topdressing may no longer be affective. Due to the cost restraints associ- ated with this material application is often restricted to localized high traffic areas, such as sidelines and soccer goal mouths. Current recommendations suggest small- particle size crumb rubber (0.05 to 2.0 mm) applied at a 0.25-inch depth (223 kg per 1,000 ft2) per application until a cu- mulative depth of 0.75 to 1.0-inch is achieved. Crumb rubber, while being substan- >> THIS PHOTO illustrates the perched water table affect that can result from applying a topdressing material with a greater amount of fine particles; fine sand, very fine sand, silt and clay, over sand with a greater proportion of coarse material. RECOMMENDATIONS When using sand topdressing to de- velop a built-up sand-capped athletic field system field managers should strive to apply a 1 inch depth of sand topdressing over a 3.5 month period, with a cumula- tive depth of 2 inches, which is attainable in as little as two growing seasons. After this depth is achieved apply 0.25-inches of sand topdressing annually, coupled with core cultivation and/or vertical mowing to mitigate organic matter accumulation. When selecting a topdressing material field managers looking to improve stabil- ity and drainage should select materials that adhere to "Topdressing Material Rec- ommendations for Athletic Field Use" (Table 1). While field managers looking to maximize drainage should select sand that conform to USGA recommenda- tions for a method of putting green construction (USGA, 2004). ■ >> Above: WHEN CULTIVATING a built-up sand-capped field with a sand depth of 2-inches or less, verticutting is an easy alternative to core cultivation that will not disrupt the soil profile. 16 SportsTurf | August 2012 Abraham Baldwin Agricultural College, Tifton, GA. Articles referenced available online. Alec Kowalewski, PhD, is an assistant professor, environmental horticulture, www.sportsturfonline.com >> CRUMB RUBBER is an excellent topdressing material for high traffic areas were sand topdressing may no longer affective; however, it is cost prohibitive ($1,000 per 1,000 lbs) in comparison to sand topdressing ($20-30 per 1,000 lbs, depending on specifications and availability).