Sustainable Crop-Livestock Integration for the System Health in the Dryland Inland Pacific Northwest

View the project final report

Commodities

• Agronomic: wheat

Practices

• Animal Production: grazing - multispecies
• Crop Production: cover crops
• Education and Training: on-farm/ranch research

Dryland wheat-fallow producers have begun switching to a direct seed tillage system for soil health benefits such as reduced runoff, increased water infiltration, increased consistency of crop stands, more and longer period of surface cover from crop residue, better soil moisture, and fewer dust clouds at planting time. However, this practice often requires increased pesticide and herbicide use. Thus, many producers are interested in economically sustainable strategies for reducing pesticide use and further improving soil health. This project is working with five producers, who typically farm using a direct seed wheat-fallow rotation, to experiment with a more biologically intensive and sustainable management system. We hypothesized that integrating cover crops and livestock will improve soil health, suppress weeds, and reduce pesticide use. 

Trials were completed in 2017 and 2018.  Treatment (cover crops with livestock grazing) had little to no effect on soil parameters such as phosphorus, potassium, magnesium, boron, zinc, or organic matter.  The treatment sites did show significant decreases in nitrate nitrogen and increased ammonium nitrate; this was likely due to the uptake of nitrogen by vegetative mass, and returns from livestock.  We observed decreases in sulfur and a slight increase in soil pH in the cover crop treatment.  Soil moisture was significantly lower in the grazed cover crop than the control at the time of soil sampling; however, there was no significant difference between plant stand establishment or plant height. Successive spring crop yield showed no significant differences between the wheat fallow control and the grazed cover crop.  Producers thought that the animals had good body condition scores when coming off the cover crops. Since project completion, producers have continued to plant cover crops.

Long-term goals of the producers and the project as they relate to the WesternSARE Program include the following:

1. Increase diversity in an agricultural system that has historically planted a single crop for 100 years.
2. Reduce pesticide and synthetic herbicide use toward more socially responsible and environmentally sound agricultural production systems.
3. Reduce long-term economic risk, protect soil resources, and increase farm viability through more holistic, sustainable, and biologically-based farming practices.