Minimizing inputs with fall seeded cover crop mixes in the high precipitation zone of the Palouse Region

View the project final report

Commodities

• Agronomic: barley, flax, peas (field, cowpeas), wheat

Practices

• Crop Production: cover crops, crop rotation
• Education and Training: on-farm/ranch research
• Production Systems: dryland farming

The integration of cover crops is gaining popularity with producers as a way to improve soil health, minimize inputs and create more resilient agricultural systems.  While cover cropping is gaining attention nationally, only a handful of producers in the Palouse region of the inland Pacific Northwest are experimenting with cover crops due to a lack of regionally specific research and resources.  To address this need, Lester Wolf Farms INC., the Palouse Conservation District and local Natural Resource Conservation Service staff worked together to develop an economically sustainable cropping system, integrating cover crops in the high precipitation zone of the Palouse region to promote soil health, and reduce synthetic fertilizers and herbicides.  This three-year project experimented with fall seeded cover crops in the traditional winter wheat-spring wheat-pulse rotation. A block design containing six strips, three business-as-usual strips (control) and three cover crop strips (treatment), was set up in all three of the traditional crops planted, resulting in 3 blocks and 18 strips. Soil physical and chemical data were collected from each strip along with crop yields and farm level inputs to calculate relative profitability.  Results were shared through field tours, stakeholder workshops, fact sheets, a peer reviewed article and a video. Outcomes included: a reduction in glyphosate application by 62%; new information on cover crops as a weed management tool was gained such as the fact that the cover crop triggered weed germination; the discovery of cover crop mixes, rates and timing in order to successfully utilize cover crops in our region; and decreased synthetic fertility needs as a result of soil biodome health.

The overarching goal of this study was to develop an economically sustainable cropping system that integrated cover crops with cash crops in the high precipitation zone of the Palouse to promote soil health, and eventually reduce or eliminate synthetic fertilizers and herbicides.

This goal was accomplished through the following objectives:

1. Assessed the effects of successfully established fall and spring cover crop mixes on weed pressure and key chemical and biological indicators of soil health.
2. Evaluated and compared the economic returns of the selected cover crop mixes vs. business-as-usual (no cover crops) in the high precipitation zone of the Palouse.
3. Developed and disseminated management recommendations for farmers based on these results through field tours, stakeholder workshops, fact sheets, a peer reviewed article and a video featuring the project that highlights successes, failures and recommendations for new adopters.