Western SARE

Dedicated to Improving Soil Health for Northwestern Growers

Doug Collins, Washington State University

As a graduate student at Washington State University (WSU), Doug Collins focused his research efforts on a topic of great interest to the region’s specialty crop growers, and one that would shape his Extension career to come: improving our understanding of complex soil processes and their role in farm productivity.

With support from a 2006 SARE Graduate Student grant, he studied the spatial variation of microorganisms and other soil properties on a local organic vegetable farm. “Many high-value specialty crop growers are increasingly interested in information about the biological status of their soil but are unsure how to sample for organisms and leverage biological data for improved, site-specific management,” Collins noted at the time.

Through the data he collected, he was able to recommend general biological sampling methods and interpretation guidelines to optimize farm productivity and profitability through improved management decisions.

Based on the graduate student project, Collins authored a fact sheet on soil sampling strategies for diverse vegetable farmers. The fact sheet encourages farmers to map the variability of soil physical properties on their farm and to account for it when conducting soil fertility sampling.

One objective of the Graduate Student grant program is to expose students to the rigors of grant writing and on-farm, applied research in order to better prepare them as future applicants for SARE’s larger, multi-year research grants. This has held true with Collins.

Now, as an Extension faculty member with WSU’s Small Farms Program, Collins has received more than $500,000 in subsequent SARE funding to conduct three additional projects aimed at improving soil management on organic farms, notably through cover crops and reduced tillage.
“We find these kinds of projects to be instrumental for developing progressive organic soil practices,” says Jim Baird of Cloudview EcoFarms, who collaborated with Collins to design one of these projects. “This information is very much needed in our agricultural world.”

Collins has received more than $500,000 in subsequent SARE funding to conduct three additional projects aimed at improving soil management on organic farms.

When Collins brought together a research and producer group, they identified a critical barrier to adopting reduced tillage: a lack of research on successful reduced-tillage practices for systems like theirs in the Northwestern maritime climate. So, his four projects have studied soil properties, tillage practices, cover crops, weed management and nitrogen management in real-world, on-farm situations. All projects have reached over 200 Washington farmers, providing useful information on managing soil on organic farms.

Farmer surveys over the course of the projects reveal that while barriers still exist, some are beginning to use aspects of reduced tillage, including terminating cover crops with flail mowers or homemade crimpers, using broad forks to open the soil for planting, and mulching with burlap sacks or straw.

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Keeping an Open Mind

Emmanuel Omondi, University of Wyoming

Dy beans, Wyoming’s fourth-largest crop by value, can suffer reduced yield and quality due to deficiencies of the micronutrients iron and zinc. This is a normal occurrence in soils with low organic matter and a high
pH, which are common in Wyoming. The most conventional solution is to add micronutrients through repeated chemical sprays, but a potentially cheaper alternative explored by a SARE-funded graduate student and some inquisitive farmers lies in something much simpler: grass.

This idea germinated when Mike and Cindy Ridenour observed this benefit of ryegrass on their farm and tested it with a 2006 SARE Farmer/Rancher grant.

“The results of the experiment were encouraging and clearly indicated that there existed some form of symbiosis between the grass and the beans,” Mike Ridenour says.

That is where University of Wyoming graduate student Emmanuel Omondi came in. Brought on to the Ridenour’s field experiment as a research assistant, Omondi saw the remarkable results and jumped on the opportunity to further the research by studying how intercropping annual ryegrass with dry beans alleviated micronutrient deficiency chlorosis and produced better yields compared to growing beans alone.

Funded by a 2008 SARE Graduate Student grant, Omondi originally focused on pH, organic matter and other soil characteristics. Looking back, he notes that this specific premise “kept his mind in a box” and limited results. However, after he finished his master’s degree and started working on his Ph.D., he had a flash of insight that opened his mind to other possibilities.

This “flash” led Omondi to consider the contribution of other soil nutrients toward iron deficiency. Further research showed that surplus nitrogen, and manganese to a degree, were responsible for the deficiency. Ryegrass reduced the concentration of these nutrients in the soil and thus alleviated the iron deficiency that reduces yields.

Omondi noted that farmers forced to spray iron sulfate two to three times per season would spend $10 to $35 per acre, money that would be saved if ryegrass could do the job just as well.

While more research is needed to make intercropping ryegrass viable commercially, it can potentially save farmers money by reducing the need to spray micronutrients such as iron sulfate. In 2008, Omondi noted that farmers forced to spray iron sulfate two to three times per season would spend $10 to $35 per acre, money that would be saved if ryegrass could do the job just as well. In addition, as a non-chemical cultural practice, intercropping ryegrass would be a welcome alternative for organic and natural bean producers, as well as for farmers in Omondi’s native Kenya.

“Cindy and I are pleased to have been a part of Dr. Omondi’s master’s and doctoral work,” Mike Ridenour says. “Through the grants from Western SARE, Emmanuel was enabled to take his enthusiasm and curiosity to expand our scientific understanding of plant-soil interactions, and to become a learned professional within the global agricultural research community.”

Now, as the research director for the long-term Farming Systems Trial at the Rodale Institute in Pennsylvania, Omondi appreciates the opportunity he had in Wyoming to bring sustainable solutions to the problems faced in conventional production systems.