ARS | Publication request: Dry pea and lentil can improve semiarid crop production

Submitted to: Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 1, 2011
Publication Date: February 4, 2012
Citation: Anderson, R.L. 2012. Dry pea and lentil can improve semiarid crop production. In: Proceedings of Colorado Conservation Tillage Association Conference, February 1-2, 2012, Burlington, Colorado. 8 pages.

Interpretive Summary: Crop production in the Central Great Plains has been transformed because of no-till. Preserving crop residue on the soil surface has improved precipitation storage in soil such that producers can minimize the need for fallow (an interval where all plant growth is prevented to save precipitation for future crop use). No-till has enabled producers to increase land productivity and net returns, as well as initiate a cycle of restoration of soil health. To further enhance this restoration of soil health, producers would like to eliminate the use of fallow completely. Dry pea and lentil are synergistic to following crops, improving water-use-efficiency of following crops. A practice of green fallow, where dry pea or lentil is grown only for 6 to 8 weeks, used in diversified rotations, may help producers develop rotations that do not require fallow. A further benefit is that yield of crops following the green fallow may be increased without needing to increase resource inputs such as fertilizer or water.

Technical Abstract: Crop diversity and no-till are changing crop production in the semiarid Great Plains. Crop diversity gains a benefit with some sequences; growth efficiency is improved, which we term synergism. For example, winter wheat water-use-efficiency is more than 30% higher in a winter wheat-corn-proso millet-dry pea rotation compared to winter wheat-fallow. Corn and dry pea affect winter wheat physiology such as water is used more efficiently. In dry regions, water supply for crop growth can be limiting without the use of fallow. However, fallow is extremely damaging to soil health. Using a green fallow approach, where dry pea or lentil are grown only 6 to 8 weeks before being killed with herbicides, improves microbial growth, N supply, and winter wheat growth such that 12- to 14-month fallow intervals are not needed for successful cropping cycles. This practice of green fallow may prevent the damage 12- to 14-month fallow normally causes in crop-fallow systems.