Utilization of cover crops is receiving a great deal of attention due to the ongoing NRCS Soil Health Initiative and the general understanding that cover crops improve soil health. Actively growing plants provide numerous benefits to the soil. However, maintaining cash crops year around is not possible in Oklahoma because the fallow periods are not long enough for maturity to grain. This is why the use of cover crops was developed to maintain active growth. Leguminous cover crops can provide the added benefit of fixing nitrogen from the atmosphere into plant available forms. The benefits listed below can provide improve performance of the following cash crop or in the case of improved soil erosion control or water infiltration provide offsite benefits in the form of decreased sedimentation of water bodies.
Potential Benefits of using cover crops:
- Soil erosion control
- Improved water infiltration
- Prevention or alleviation of compaction
- Improved nutrient cycling
- Nitrogen Fixation
- Reduced soil temperature and water evaporation from the soil surface.
- Improve soil microbial diversity
- Reduced weed populations during fallow periods.
Potential Negative Impacts of using cover crops:
- Increased Labor and equipment costs associated with planting cover crops
- Soil water use during cover crop growth, which can deplete subsoil moisture if recharging rains are not experienced after termination of cover crops
- Limitations on pre-emergent herbicide use because many common pre-emergent herbicides will prevent growth of cover crop species.
The following links provide current information on cover crops and their use on Oklahoma cropping systems.
Managing Cover Crops Profitably http://www.southernsare.org/Educational-Resources/Books/Managing-Cover-Crops-Profitably-3rd-Edition
Using Sunn Hemp as a Cover Crop in Oklahoma http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-9234/PSS-2273.pdf
Benefits of using Cover Crops in Oklahoma No-Till http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-8891/PSS-2161web.pdf