*To be entered in by P.I.*
*To be entered in by P.I.*
Determine cover crop seed mix
Okanogan Conservation District (OCD) and producers developed a seed list for cover crops based on results of previous observations and trials. A seeding rate of 20 seeds / square foot was targeted to achieve coverage of field without reducing moisture excessively. Species were chosen based on diversity, palatability, and productivity.
Each of the three cooperator sites is considered a statistical block. Within each block, two treatments (grazed cover crop and fallow control) are implemented in a paired design with four replications. Producers drill planted the cover crop mix in June of 2017. Each producer planted 30 acres of cover crop leaving four “skips” (Figure 1). These skips, approximately 40’x100’, acted as control plots and were fenced off with T posts and electric wire (Figure 2). Immediately adjacent to the controls, we created paired plots in the cover crop measuring 40’ x 100’ (Figure 1). All plots were marked with GPS points. Livestock had access to the grazed cover crops, but not the wheat-fallow control.
Above ground biomass, in one meter square quadrants, was recorded and samples collected at two sites before and after grazing (Figure 2). At the third site, no biomass data were collected because OCD was not notified when cattle were placed on the field. Fields were grazed with cattle at appropriate times for each field for between 3-10 days depending on the forage available and number of livestock used (Figure 2). Cow/calf pairs were used at two sites and stockers at the third. Remaining cover crop biomass was recorded after grazing. Cover crops at all sites were terminated after grazing using a mix of roundup and 2,4-D. Poole and Bunch sites were planted into soft white winter wheat in September 2017. The third site will be planted into a spring crop.
Soil samples were collected from each plot in August using 4” diameter augers (Figure 2). Samples were taken at depths of 0-6”, 6-12”, 12-24”, 24-36”. Soils were analyzed for moisture, OM, pH, available nutrient contents, and microbial activities by Soil Test Farm Consultants in Moses Lake, and by WSU. Above ground biomass was weighed and dried by the NRCS Plant
Materials Center and then sent to WSU for nutrient analysis. Final soil and biomass analyses are underway. Statistical analysis of the first year’s results will be conducted in winter of 2018. A faculty member and graduate student in the WSU Center for Center for Interdisciplinary Statistical Education and Research (CISER) have received soil data from this study and met with Michel and Carpenter-Boggs. The CISER consultants are currently building a set of R programs to analyze these data.
Educational & Outreach Activities
- Publications, Handouts, Other Text & Web Products:
- 2 Facebook posts on Okanogan Conservation District’s page – 50 views
- Outreach & Education Activities:
- Field tour on soil health (including cover crops and grazing) in dryland systems –20 attendees: May 2017 – Lincoln, Douglas, and Okanogan Co.
- Field tour for cover crops and grazing –55 attendees: June 2017 – Douglas Co.
Cover Crops in wheat fallow
Livestock grazing covers
- Short-Term: Increase knowledge by dryland wheat fallow producers and regional ag professionals, based on field trials and analysis. Knowledge includes appropriate cover crop mixes, seeding rates, and management; and how incorporating cover crops into crop rotation will affect moisture, yield, soil nutrients, and livestock weight gain. Information will provide producers with an understanding of how cover crops are impacting their production system.
- Intermediate-Term: Dryland wheat-fallow producers are increasingly interested in adding diversity to their rotation. Early adopters incorporate cover crops and grazing into their operations. The addition of cover crops and livestock provide farmers with additional resources and tools to diversify rotations, break up weed and disease patterns, improve soil health, and reduce herbicide inputs.
- Long-Term: Producers use new knowledge and tools to improve soil health and economic sustainability in their production system. Diversification is implemented to improve soil health and help mitigate long term risk against drought and climate change.