TURFGRASS AND TRAFFIC
Ideal leaf tensile strength is achieved through proper irrigation . Photo by Ben Pease , Ph . D . to improve the playing quality and percent cover of perennial ryegrass ( PR ) under traffic stress . Frequent sand topdressing and aeration have been recommended to maintain acceptable playing conditions for high-traffic athletic fields . For example , Kentucky bluegrass ( KBG ) has higher plant density and rooting under traffic when sand topdressed , with fall shoot density and surface shear strength of KBG under traffic increased by summer topdressing applications . The best advice when using sand topdressing is be consistent . Use sand compatible with the root zone , and stick to a schedule to avoid creating layers in the soil profile , which could hinder drainage and root growth , thus making the field less traffic tolerant .
Crumb rubber topdressing has also been shown to increase traffic and wear tolerance in a KBG and PR mix when applied at rates of at 700 lbs . per 1,000 ft 2 , and has been shown to be more effective than sand for increasing trafficked KBG percent cover . In the transition zone , turfgrass wear tolerance of both cool- and warm-season turfgrasses was improved by crumb rubber topdressing . Bermudagrass traffic tolerance is improved by topdressing crumb rubber at depths of 0.25-0.75 inches . Topdressing with crumb rubber could reduce abrasive stress of sand topdressing , but long-term effects on the rootzone have not been addressed .
FERTILITY AND IRRIGATION Traffic tolerance is often correlated to leaf tensile strength or leaf density , although the correlation changes by species . The same concept is applicable for leaf water content , total non-structural carbohydrates , and leaf strength . In the case of PR , most traffic-tolerant cultivars have fine leaf texture , lower total cell wall content , and lower lignin content . Phenotypic classifications of KBG have been compared , finding that Compact-Midnight and Julia types were best performers under high traffic amounts .
Ideal leaf / plant density is achieved through proper fertility . While the exact amounts vary by species and location , guidelines are available . Cool-season fields need 4.5-5.5 lbs . of N per 1,000 ft2 per year , while warm-season fields need 5.0- 7.0 lbs . of N per 1,000 ft2 depending if they are overseeded for winter use . Trafficked athletic field turfgrass will not recover from traffic damage without additional nitrogen fertilization ; and a simple lack of nitrogen is sportsfieldmanagementonline . com September 2021 | SportsField Management
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