Pulse Brain · Growing Health Evidence Index
Tier 3 — Observational / field trialPeer-reviewed

Yield and water use of grain legumes intercropped with spring canola in Eastern Washington

Garett C. Heineck, K. L. Smith, Haly L. Neely, Joaquin Casanova, Diana Salguero, Francisco Gonzalez‐Tapia, Sarah R. Peery, Lynne Carpenter‐Boggs, John P. Reganold, David R. Huggins

Agrosystems Geosciences & Environment · 2025

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Summary

This three-year field trial evaluated intercropping grain legumes (peas and chickpeas) with spring canola in the Palouse watershed, comparing sole-crop and intercrop systems. Legume–canola intercrops demonstrated moderate overyielding (land equivalency ratios of 1.14–1.15) with differential species dominance: canola dominated chickpea intercrop whilst peas predominated in pea–canola intercrops. Intercrops increased soil water depletion at deeper soil depths compared to legume monocultures, with chickpeas consuming the most shallow-depth water; winter wheat yields were unaffected by the preceding intercrop treatment.

UK applicability

Findings are broadly relevant to UK arable farming in regions with similar rainfall patterns, particularly in drier eastern and central areas where water use efficiency and legume integration are important. However, differences in photoperiod sensitivity, frost risk, and soil types may require localised validation before adoption in UK cropping systems.

Key measures

Land equivalency ratios; grain yield; plant height; branch count; soil water consumption at shallow (0–70 cm) and deep (70–130 cm) soil depths; winter wheat yield and grain quality

Outcomes reported

The study measured land equivalency ratios, yield components, and soil water consumption at two soil depths (0–70 cm and 70–130 cm) for sole-cropped and intercropped canola with chickpeas or peas, followed by winter wheat. Winter wheat yields and grain quality were assessed in the subsequent season.

Theme
Farming systems, soils & land use
Subject
Agroforestry & intercropping
Study type
Research
Study design
Field trial
Source type
Peer-reviewed study
Status
Published
Geography
United States
System type
Mixed farming
DOI
10.1002/agg2.70167
Catalogue ID
BFmowc29c7-gf0z1g

Topic tags

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