TURFGRASS AND TRAFFIC

By Ben Pease , Ph . D .

Athletic field traffic management . This topic can cause an argument faster than politics at Thanksgiving . But it is the focus of sports field management at all levels . The playability ( traffic tolerance ) and aesthetics ( traffic recovery ) are likely factors in every turf management decision , and have become more important as interest in athlete and field safety increases .

Present-day turfgrass managers are pushing turfgrass stands to perform at higher standards — and for longer periods — than previously thought possible , due to turf genetic improvements , advancements in turf culture technology , and pressure from end users for “ better ” conditions . Because of these demands , turfgrass stress tolerance research regarding heat , drought or salinity stress has increased during the past two decades . This is not the case with traffic or wear stress . Often there are minimal changes a turfgrass manager can implement to alter the type , volume or pattern of traffic stress — aside from a complete ban of traffic . For this reason , traffic or wear stress must be tolerated by the turfgrass and planned for by the turfgrass manager .

Based on current understanding , improving traffic tolerance is mostly a function of turfgrass species and cultivar selection — often only addressed during a sports field renovation . If renovation is not an option , improving traffic tolerance is mostly a function of regulating traffic frequency or severity , and adopting ideal cultural practices . Because traffic regulation is often not a popular option when proposed to athletic coaches , turfgrass selection and cultural practices are the primary means of mitigating traffic-induced stress .

Use sand compatible with the root zone and stick to a schedule to avoid creating layers in the soil profile . Photo courtesy of Nick Christians , Ph . D .

Let ’ s look at what the research says by various cultural practice categories , and determine how that relates to guidelines you can follow to best prepare your fields for traffic events .

ROOTZONE CHARACTERISTICS AND AERATION Traffic stress is exacerbated under compacted soil conditions . Finetextured soils are more prone to compaction , resulting in less recuperative potential due to already weakened and thinned turf plants . Regardless of rootzone composition , athletic events will result in soil compaction , especially if soil moisture content is higher than ideal . Because sand provides good drainage and does not compact , it is often preferred for heavily trafficked sites . It has been shown that soil type affects percent cover of trafficked athletic fields . Hybrid bermudagrass maintained higher percent turf cover for a longer period when grown on a USGA sand field compared to a silt loam field .

Overall , a sand-based field will perform better than a native soil field , but , in both situations , having adequate drainage and following a strict aeration schedule will help turf withstand traffic damage . For coolseason fields , hollow-tine aeration is best performed in the spring , and solid-tine aeration during the summer and fall months when fields are in heavy use . For warm-season fields , hollow-tine aeration should not occur until the turf has initiated spring growth .

TOPDRESSING Sand topdressing , in conjunction with nitrogen fertility , has been shown

30 SportsField Management | September 2021 sportsfieldmanagementonline . com