Regenerative Agriculture: Importance of crop rotations in maximizing crop diversity
Many producers practicing regenerative agriculture have adopted the term resilience into their working definition. Merriam-webster defines resilience as “an ability to recover from or adjust easily to misfortune or change.” Based on this definition, resiliency is a common goal for the agriculture industry.
In the previous article, the preservation of soil moisture, reduction of erosion and temperature moderation was discussed through the integration of minimum tillage practices. This article will discuss the second principle of regenerative agriculture: using a strong crop rotation to contribute to increased resiliency. For example, the use of residual soil moisture and nutrients by crops seeded the following year is one benefit of a diverse crop rotation. While an integral part of the regenerative agriculture movement, use of a diverse crop rotation has become a good practice that can be recommended for any operation regardless of whether they are reaching for regeneration or just good farming.
Many producers in Saskatchewan have already been diversifying cropping rotations by adding pulses to their cereal and oilseed rotations. Regenerative agriculture, with a focus on crop diversity, allows for more years between crops, which in turn benefits disease management as allows more time for soil-borne pathogens to decrease and ensure a healthier crop the next time it is part of the rotation. Perennial forage crops and annual forage crops are becoming more common in rotations across the prairies as one method to address the many production-related changes producers are facing. Research in western Canada has linked higher soil compaction to more plant stress when compared to non-compacted soil. Compaction can also increase the risk and severity of root rots, including Aphanomyces. Therefore, when designing crop rotations, it is important to include a variety of root systems which will help to prevent soil compaction.
When integrating perennial and annual forages into rotations, it’s important to consider factors such as available moisture, desired outcomes, field restrictions and future crops. A study at the Western Beef Development Centre observed that soil water content was notably reduced in fields of terminated alfalfa grass mixtures when compared to terminated fields of grass monocultures. The same study noted that, despite the reduction in soil moisture, alfalfa grass mixtures delivered a nitrogen benefit to the following barley crop, leading to increased yield and potential market value.
Varying between crops with differing root depths can also improve soil water use. A study in Swift Current found that growing deeper-rooted crops, such as canola and wheat, following shallow-rooted crops, such as pulses, resulted in increased overall soil water use efficiency and soil water storage. Being that water is a primary limiting factor in Saskatchewan agriculture, efficient use of the moisture resources available aids in building resiliency into the industry.
Our next article will discuss maintaining living roots and keeping the soil covered and maintaining living roots year-round. To speak with an extension specialist near you regarding regenerative agriculture, contact the Agriculture Knowledge Centre at 1-866-457-2377.