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Providing evidence to improve practice

Individual study: Stability of exotic annual grasses following grass control and native reseeding efforts in southern 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.

Use herbicide 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 using grass-specific herbicide to control invasive grass species reduced the cover of invasive grasses but had no effect on native forb cover. After one year, areas where herbicide was applied had lower cover of invasive grass species (37%) than areas where no herbicide was applied (52%). After five years, cover of invasive grasses in herbicide treated areas (12%) was still lower than in areas not treated with herbicide (31%). After one year, cover of native forbs was not significantly different in areas where herbicide had been sprayed (4%) and in unsprayed areas (2%), but was higher in sprayed plots in one of five subsequent years (sprayed: 0–32% cover; unsprayed: 1–39% cover). Twenty 1 m2 plots were sprayed with the herbicide Fusilade II in 1999 and 2000, while twenty other plots were not sprayed. Plant cover in the plots was assessed annually in 1999–2004.

(Summarised by Phil Martin)