The effect of grass leaf height on the impact behaviour of natural turf sports field surfaces

Abstract

The effect of three grass leaf height treatments (50 mm, 25 mm, < 1 mm) of two sports field rootzones (clay loam, sand) was assessed under controlled conditions using the 0.5 kg and 2.25 kg Clegg Impact Soil Testers (CIST) and the Dynamic Surface Tester (DST) device. Results were dependent upon the test device, impact energy, and drop number of the impact. The presence of grass was shown to be more important than specific grass heights in regulating impact behaviour, with no differences detected between 50 mm and 25 mm treatments. Peak deceleration was reduced (P < 0.05) by the presence of grass (50 mm and 25 mm treatments) for drop one, but not drop three of the 0.5 kg CIST missile, indicating grass leaves absorb some impact energy on lower energy single impacts but not when leaves are flattened under repeated loading. There was no difference in peak deceleration of the higher energy 2.25 kg CIST among leaf treatments for first drop, but was significantly lower (P < 0.05) for third drop on the < 1 mm tre...