Trade-offs between winter cover crop production and soil water depletion in the San Joaquin Valley, California

  • Published source details Mitchell J.P., Shrestha A. & Irmak S. (2015) Trade-offs between winter cover crop production and soil water depletion in the San Joaquin Valley, California. Journal of Soil and Water Conservation (SWCS), 70, 430-440.


This study is summarised as evidence for the following.

Action Category

Water: Grow cover crops in arable fields

Action Link
Mediterranean Farmland
  1. Water: Grow cover crops in arable fields

    A replicated, randomized, controlled study in 2012–2014 in a mostly rainfed field in the Central Valley, California, USA, found less water in soils with winter cover crops, compared to winter fallows. Water availability: Over the winter, less water was found in soils with cover crops, compared to fallows, in some comparisons (2013: 5.3 cm less water; 2014: 0.67 less; number of comparisons not clearly reported). This was because water was lost from soils with cover crops, but gained in soils with fallows. Methods: There were three plots for each of three cover crops (legumes: 45% Vicia faba, 35% Pisum sativum, and 20% V. sativa; legumes and triticale: 40% P. sativum, 30% V. sativa, and 30% Tritocosecale; or brassica: 45% Brassica juncea, 40% Sinapsis alba, and 15% Raphanus sativus) and there were three fallow plots (kept bare with herbicide). Each plot was 10 x 30 m. All plots were irrigated only to establish the cover crop (10 cm/year). Plots with cover crops were fertilized (112 kg N/ha) and seeds were sown in November. Water content was measured twice/week in January–March (0–90 cm depth).


Output references
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.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 19

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.

Who uses Conservation Evidence?

Meet some of 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