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Individual study: Wheat Yields, Nitrogen Uptake, and Soil Moisture Following Winter Legume Cover Crop vs. Fallow

Published source details

McGuire A.M., Bryant D.C. & Denison R.F. (1998) Wheat Yields, Nitrogen Uptake, and Soil Moisture Following Winter Legume Cover Crop vs. Fallow. Agronomy Journal, 90, 404-410


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Water: Grow cover crops in arable fields Mediterranean Farmland

A replicated, randomized, controlled study in 1994 in an irrigated wheat field in the Sacramento Valley, California, USA, found less water in soils with winter cover crops, compared to fallows. Water availability: Less water was found in soils with cover crops, compared to fallows (1.2–3.0 cm less water, 0.16–0.25 vs 0.20–0.35 m3 water/m3 soil, 0–90 cm depth). Methods: Legumes were grown as winter cover crops in some subplots, and other subplots were fallows (the number and size of the subplots was not clearly reported, but the main plots were 64 x 64 m). Half of the main plots were irrigated. In the wheat-growing season, half of the subplots were fertilized, but the cover crops and fallows were not fertilized. Soil samples were collected in August 1994 (0–90 cm depth), and water content was calculated by drying and weighing the soil (assuming a bulk density of 1.68 g/cm3).