Use herbicides to remove invasive plant species

How is the evidence assessed?

Study locations

Key messages

  • One replicated, randomized, controlled study in the USA found no effect of invasive plant control using herbicide on the total native plant species richness.


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 replicated, randomized, controlled study in 2000-2005 in temperate broadleaf forest in Ohio, USA (Hochstedler et al. 2007) found no effect of control of invasive garlic mustard Alliaria petiolata on native plant species richness and diversity. Species richness was similar between treatments in both old-growth (sprayed: 8.7; unsprayed: 8.0 species/plot) and second-growth forests (sprayed: 10.6; unsprayed: 10.5). The same was true for species diversity (Shannon’s index old-growth: sprayed 1.7, unsprayed 1.4; second-growth: sprayed 2.0, unsprayed 2.0). Data were collected in 2005 in 25 sprayed (garlic mustard individuals sprayed with glyphosate herbicide Roundup© PRO at the start of winter in 2000-2004) and 25 unsprayed plots (1×1 m). Plots were randomly placed in each of 16 ha second-growth and 20 ha old-growth forest sections.

    Study and other actions tested
Please cite as:

Agra, H., Schowanek, S., Carmel, Y., Smith, R.K. & Ne’eman, G. (2020) Forest Conservation. Pages 323-366 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

Forest Conservation

This Action forms part of the Action Synopsis:

Forest Conservation
Forest Conservation

Forest Conservation - Published 2016

Forest synopsis

What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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