Apply herbicide and remove plants to control grass

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Study locations

Key messages

  • One randomized, replicated, controlled, paired study in the USA found that areas sprayed with herbicide and weeded to control non-native grass cover had higher cover of native grasses and forbs than areas that were not sprayed or weeded, but not a higher number of native plant species. The same study found that spraying with herbicide and weeding reduced non-native grass cover.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A randomized, replicated, controlled, paired study in 2005–2008 in creosote bush shrubland invaded by non-native grasses in California, USA (Steers & Allen 2010) found that spraying with herbicide, followed by weeding, decreased invasive grass cover, increased the cover of native grass and forb species, but did not increase the number of annual plant species. Areas that were sprayed with herbicide and were weeded had lower non-native grass cover (0–38%) than areas that were not sprayed or weeded (40–65%). Also, areas that were sprayed with herbicide and weeded had lower had higher cover of native grass and forb species (20–87%) than areas that were not sprayed or weeded (13–36%). However, the number of native annual plants was not significantly different in areas that had been sprayed with herbicide and weeded (4–18%) and unsprayed and unweeded areas (23–37%). In January 2006 and 2008 twelve 8 m x 8 m plots were sprayed with the grass specific herbicide Fusilade-II and then weeded by hand while twelve other plots were not sprayed with herbicide or weeded. Plant cover was recorded in March-April 2006 and 2008 in 0.5 m2 quadrats located in each plot.

    Study and other actions tested
Please cite as:

Martin, P.A., Rocha, R., Smith, R.K. & Sutherland, W.J. (2020) Shrubland and Heathland Conservation. Pages 483-525 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Shrubland and Heathland Conservation

This Action forms part of the Action Synopsis:

Shrubland and Heathland Conservation
Shrubland and Heathland Conservation

Shrubland and Heathland Conservation - Published 2017

Shrubland and Heathland synopsis

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