Rake to control grass

How is the evidence assessed?
  • Effectiveness
    30%
  • Certainty
    20%
  • Harms
    12%

Source countries

Key messages

  • A randomized, replicated, controlled, paired study in the USA found that cover of both invasive and native grasses, as well as forbs was lower in areas that were raked than in areas that were not raked, but that the number of annual plants species did not differ.

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 that was invaded by non-native grasses in California, USA (Steers & Allen 2010) found that raking reduced invasive grass cover but did not increase the number of annual plant species, and also reduced the cover of native grasses and forb species in two of four cases. In four of four cases areas that were raked had lower non-native grass cover (36–39%) than areas that were not raked (60–65%). In four of four cases the number of annual plant species in areas that had been raked (2–4 species/plot) did not differ significantly from the areas that had not been raked (3–4 species/plot). However, in two of four cases cover of native grass and forb species was lower in areas that had been raked (4–18%) than in areas that had not been raked (23–37%). In January 2006 and 2008 twelve 8 m x 8 m plots were raked to remove invasive grasses while twelve other plots were not raked. 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. (2018) Shrubland and Heathland Conservation. Pages 447-494 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2018. 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

What Works in Conservation

What Works in Conservation

What Works in Conservation assesses the research looking at whether interventions are beneficial or not. It is based on summarised evidence in synopses, on topics such as amphibians, bats, biodiversity in European farmland, and control of freshwater invasive species. More are available and in progress.

More about What Works in Conservation

Download free PDF or purchase
Our Journal: Conservation Evidence

Our Journal:
Conservation Evidence

A unique, free to publish open-access journal publishing research and case studies that measure the effects of conservation actions.

Read latest volume: Volume 16

Special issues: Amphibian special issue

Go to the Journal

Subscribe to our newsletter

Please add your details if you are interested in receiving updates from the Conservation Evidence team about new papers, synopses and opportunities.

Who uses Conservation Evidence?

Meet the evidence champions

Endangered Landscape Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Butterfly Conservation People trust for endangered species Vincet Wildlife Trust