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Cover Cropping

 

Cover crops are receiving renewed interest, but remain underutilized in contemporary U.S. agriculture.  Cover crops can help conserve nutrients, control soil erosion, improve water infiltration and quality, reduce weed and pest pressure, increase biodiversity, and enhance soil health.  Many plants can be used as cover crops, including rye, clover, sudangrass, mustard, buckwheat, and lupine.  They can be grown between cash crops when soil would normally be bare, or integrated into cash crops through relay planting or intercropping.  There is considerable information on cover crops from prior to the 1950s that is applicable today.  In addition, current research and experience with cover crops is opening opportunity for new ideas such as direct seeding grains into cover crops and cover crops for bioremediation of soil-borne diseases.

Featured Publications

Farmer-to-Farmer & Rancher-to-Rancher Case Studies Series

Authors include: Yorgey, G., Borrelli, K., Painter, K., Davis, H., Hall, S., Hudson, T., Neibergs, S., Reeves, M., Kruger, C., McGuire A., Finkelnburg, D., Roe, D., Brooks, E., and Kantor, S. 2016-2019. PNW Extension Publications and videos. These series explore strategies that innovative regional farmers and ranchers are using that enhance resilience to climate change and other future challenges. Case studies highlight producers in dryland and irrigated annual cropping, rangeland, and dairy production systems. Practices relate to soil health, diversification, responsive management, and many others.

Video: Reduced tillage in organic vegetable production

Sullivan D. and D.P. Collins. 2018. WSU Extension Video. This video is intended for organic vegetable producers and agricultural professionals, especially in the maritime northwest. Techniques and findings from recent research are shared to assist producers in trialing reduced tillage systems. The video covers the concept of reduced tillage organic agriculture, cover crop and weed management, and specialized equipment.

Rotational Diversification and Intensification

Kirby, E., W. Pan, D. Huggins, K. Painter, P. Bista. 2017. Chapter 5 In Yorgey, G. and C. Kruger, eds. Advances in Dryland Production Systems in the Pacific Northwest. Washington State University Extension, Pullman, WA.

Advances in Dryland Farming in the Inland Pacific Northwest

Georgine Yorgey and Chad Kruger, Eds. 2017. Washington State University Extension. Pullman, WA.

Soil physical properties, nitrogen, and crop yield in organic vegetable production systems

Cogger, C, A. Bary, A. Fortuna, L. Myhre, and D.P. Collins. 2016. Agronomy Journal. 108:1142-1154

Cover crop effects on light, nitrogen, and weeds in organic reduced tillage

Wayman, S., C. Cogger, D. P. Collins, C. Benedict, I. Burke, and A. Bary. 2015. 39:6, 647-665, DOI: 10.1080/21683565.2015.1018398

The influence of cover crop variety, termination timing, and termination method on mulch, weed cover, and soil nitrate in organic reduced-tillage

Wayman, S., C. Cogger, C. Benedict, I. Burke, D. P. Collins, and A. Bary.  2014. Renewable Agriculture and Food Systems. FirstView: 1-11. http://dx.doi.org/10.1017/S1742170514000246.

Soil Fertility in Organic Systems: A Guide for Gardeners and Small Acreage Farmers

Collins,D. C. Miles, C. Cogger, R. Koenig. 2013.  Pacific Northwest Extension Publication PNW646.

Reduced Tillage on Organic Farms Virtual Field Day

WSU researchers and extension educators are researching different methods for reducing tillage in organic vegetable production. This video demonstrates termination of barley and vetch cover crops with a roller/crimper and flail mower.

Mustard Green Manures

On-farm research has been conducted since 1999 to determine the benefits of mustard green manures and to improve their effectiveness. They are being used in irrigated regions of Eastern Washington to improve soil quality, control wind erosion, and manage soilborne pests.

Additional Publications

Potential nitrogen contributions from legumes in Pacific Northwest apple orchards

Mullinix, K. and Granatstein, D. 2011. Intl. J. Fruit Sci. 11:74-87.

Cover crops in orchards and vineyards

WSU Tree Fruit Research and Extension Center webpage. Contains links to additional resources and presentations.

Influence of orchard floor management and compost application timing on N partitioning in organically managed apple trees

TerAvest, D., J.L. Smith, L. Carpenter-Boggs, L. Hoagland, D. Granatstein, and J.P. Reganold. 2010. HortScience. 45:637-642.

Sustainability trade-offs in organic orchard floor management

Granatstein, D., Wiman, M., Kirby, E., Mullinix, K. 2010. Acta Hort. 873:115-122.

Research knowledge and needs for orchard floor management in organic tree fruit systems

Granatstein, D. and E. Sanchez. 2009. Intl. J. Fruit Science 9:257-281.

Cover Crops Influence Meadow Vole Presence in Organic Orchards

M. R. Wiman, Kirby, E. M., Granatstein, D. M., Sullivan, T. P. HortTechnology July–September 2009 19(3).

Comparing tillage and mulching for organic orchard performance

Wiman, M., Kirby, E., Granatstein, D., Mullinix, K. 2008. Poster presented at 2008 BIOAg Research Symposium.

Mulching options for Northwest organic and conventional orchards

Granatstein, D. and K. Mullinix. 2008. HortScience 43(1):45-50.

Effects of Ground Cover Management Strategies on Yield and Nitrogen Supply in Organic Apple Production Systems

Poster presentation – BIOAg Research Symposium 2008.

Cover Crops as a Floor Management Strategy for Pacific Northwest Vineyards

Olmstead, M. 2006. EB2010, WSU Extenson.

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