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Providing evidence to improve practice

Individual study: The effects of litter removal and soil disturbance on exotic and native grasses and forbs in southern California coastal sage scrub, Shipley Reserve, California, USA

Published source details

Cox R.D. & Allen E.B. (2008) Stability of exotic annual grasses following restoration efforts in southern California coastal sage scrub. Journal of Applied Ecology, 45, 495-504

This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Cut/mow to control grass Shrubland and Heathland Conservation

A randomized, controlled study in 1999–2004 in sage scrub habitat in California, USA (Cox & Allen 2008) found that mowing to control invasive grass species had no effect on native forb cover and while it initially reduced the cover of invasive grasses, this subsequently increased. One year after mowing, cover of native forbs did not differ from mown and unmown plots (1%) and after five years cover was still not significantly different between mown (5%) and unmown plots (3%). Two years after mowing, mown plots had lower cover of invasive grass species (12%) than unmown plots (18%). However, after five years, cover of invasive grasses increased in mown plots (23%) and was not significantly different to that found in unmown plots (33%). Twenty 1 m2 plots were mown annually in 1999-2001, while twenty other plots were not mown. Plant cover in the plots was assessed annually in 2000-2004.

(Summarised by Phil Martin)