Mixed Grain Intercropping and Variable Rate Seeding

Mixed grain intercropping has become a commercially significant practice in the production of grains, oilseeds, and pulse commodities on the Canadian Prairies and U.S. Northern Plains during the past decade. Mixed grain intercropping entails the seeding, growing, and harvesting of two or more cash crop simultanously. The mixed grain is then separated after harvest and marketed as individual commodities. While intercropping has various historical and current uses in the region, mixed grain intercropping is a relatively new strategy for cash crop diversification. Mixed grain intercropping is not suitable for every situation, but it does have the potential to provide agronomic and financial benefits when compared to monocrop commodity production. Further information on mixed grain intercropping can be found here.

Variable rate seeding is becoming more common on the Canadian Prairies and U.S. Northern Plains thanks to its potential to reduce seed costs and increase yield. Variable Rate Seeding requires the establishment of zones based on landscape position, soil characteristics, and previous crop year performance. It takes a significant amount of working knowledge of a field’s topographical and soil characteristics and mapping work to establish zones and build agronomic presciptions based on these zones. At the same time, seeding equipment must have the capability to change seeding rates on the fly based on zone prescriptions along with double or triple shoot openers on drill row units (with appropriate plumbing from the seed tanks), and two or more seed tanks. Further information on variable rate seeding can be found here.

A small number of farm operations on the Canadian Prairies and U.S. Northern Plains have combined mixed grain intercropping with variable rate seeding. The oat-pea combination is especially well-suited to variable rate seeding. Peas can be favored in the stand in drier areas while oats can be favored in wetter areas. Variable seeding rates for oats and peas should reflect different topographical and soil conditions across a field. When applied appropriately, variable rate seeding can translate into lower overall seed costs and higher overall yields. The same principles could be applied to other intercrop combinations such as lentil-pea-canola or chickpea-flax.

Mixed grain intercropping requires changes to a farm’s production systems and grain handling practices while variable rate seeding requires seeding equipment modification and well-developed field zone maps. But in the right situation, the merging of mixed grain intercropping and variable rate seeding can provide a significant enough financial advantage to make combining these practices worth the time, cost, and labor.

Oat-Pea Mixed Grain Intercropping

Mixed grain intercropping has become a commercially significant practice for the production of grains, oilseeds, and pulses on the Canadian Prairies and US Northern Plains. Mixed grain intercropping entails growing two or more cash crops together, harvesting at the same time, separating post-harvest and marketing the crops separately. This form intercropping is one way of increasing cash crop diversity. While intercropping has various historical and current uses in the region, mixed grain intercropping is a relatively new strategy for cash crop diversification. Most innovation in mixed grain intercropping practices across the region has been driven by farmers themselves during the past decade.

While mixed grain intercropping may not be appropriate in all situations, it does have the potential to provide a number of agronomic and financial benefits when compared to growing grains, oilseeds, and pulses as monocrops. Proven mixed grain intercrop combinations include chickpea-flax, pea-canola, or wheat-flax. The oat-pea combination is less commonly grown and therefore its distinct advantages and disadvantages are not as clear. In 2020, a team of researchers from South East Research Farm, General Mills, and Agriculture and Agri-Food Canada conducted a study focused specifically on the oat-pea mixed intercrop combination. The study uses farmer interviews, on-farm trials, and small plot trials to better understand how this combination is being used in production systems across the Canadian Prairies and Northern US Plains.

Study findings were released in public report (link) in late May 2021. The report is meant to be a resource to individuals and organizations interested in the ways in which the oat-pea combination or mixed grain intercropping more broadly can be integrated into production ag. systems.