Action

Pest regulation: Use crop rotations

How is the evidence assessed?
  • Effectiveness
    55%
  • Certainty
    20%
  • Harms
    0%

Source countries

Key messages

Pest regulation (0 studies)

Crop damage (0 studies)

Ratio of natural enemies to pests (0 studies)

Pest numbers (1 study): One replicated, randomized, controlled study from Australia found less weed biomass in plots with a canola-wheat sequence, compared to a wheat-wheat sequence.

Natural enemy numbers (0 studies)

Implementation options (1 study): One replicated, randomized, controlled study from the USA found similar amounts of weed biomass in plots with four-year or two-year crop rotations.

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 1994–1998 on an irrigated, arable farm near Davis, California, USA, found similar amounts of weed biomass in plots with four-year or two-year crop rotations. Implementation options: Similar amounts of weed biomass were found in plots with four-year or two-year crop rotations (4–273 vs 140–467 kg dry weight/ha). Methods: A four-year rotation (tomato, safflower, corn and wheat, beans) was used on 16 plots (four plots for each phase, each year), and a two-year rotation (tomato, wheat) was used on eight plots (four plots for each phase, each year). Each plot was 68 x 18 m. Fertilizer and pesticide were used on all plots. Weeds were sampled in the tomato plots, at harvest, in 1994–1998.

    Study and other actions tested
  2. A replicated, randomized, controlled study in 2010–2011 in a rainfed field in Western Australia found less weed biomass in plots with a canola-wheat sequence, compared to a wheat-wheat sequence. Pest numbers: Less weed biomass was found in plots with a canola-wheat sequence, compared to a wheat-wheat sequence (36 vs 43 g/m2). Methods: Wheat or canola was grown on three plots each in 2010, and wheat was grown on all plots in 2011. Each plot was 1.4 x 40 m. Fertilizer (150 kg/ha/year) and herbicide were used on all plots. Weeds were sampled at the end of 2011.

    Study and other actions tested
Please cite as:

Shackelford, G. E., Kelsey, R., Robertson, R. J., Williams, D. R. & Dicks, L. V. (2017) Sustainable Agriculture in California and Mediterranean Climates: Evidence for the effects of selected interventions. Synopses of Conservation Evidence Series. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Mediterranean Farmland

This Action forms part of the Action Synopsis:

Mediterranean Farmland
Mediterranean Farmland

Mediterranean Farmland - Published 2017

Mediterranean Farmland synopsis

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