Breaking down relay cropping with Dr. Jennifer Wells

Most farmers on a soil health journey are continuously looking for new innovative ideas and production practices to maximize their labor, land and capital more efficiently, while protecting the environment.  Relay cropping is a technique that some growers are utilizing to do just that.  What is relay cropping?  And what are its pros and cons?
 
What is relay cropping?
Relay cropping is a version of double cropping, where the second crop (either cash or cover crop) is planted into the established first crop before it is harvested, rather than waiting until after harvest as in true double-cropping system.¹ When thinking of relay cropping, it is easiest to think of a relay race.  Just as a runner passes the baton to the next runner while both in motion and never stopping, roots of the second crop establish prior to the initial crop root growth termination.  For example, seeding a rye cover crop in the fall and then planting soybeans into that established cover crop in the spring.  The rye can then be terminated or harvested after soybean planting.
 
Pros of relay cropping
There are many potential advantages of relay cropping.  One is that it can increase land use efficiency by providing a crop in the off season and increase profit potential per acre due to selling two crops instead of one (if  second crop is harvested and not cover).  Due to the flexibility of the planting window, it can allow a grower to plant the relay crop in a timelier manner rather than waiting until after harvest.  This is especially helpful in the northern part of the US where the growing window is shorter and allows for higher use efficiency of radiation prior to initial crop harvest.  It can help increase water efficiency by utilizing available soil moisture at emergence of the relay crop due to shaded and cooler conditions under the crop canopy.  In some cases, relay cropping can reduce weed pressure by having healthy living plant tissue in the ground year round and suppressing weed emergence.  Quite possibly the most important advantage of incorporating relay cropping into a farming operation is the overall benefit to soil health.  Having continuous living roots in the ground helps improve soil texture, structure, overall biological activity and decreases erosion.²
 
What are the cons?
As with anything in farming, relay cropping does come with its own set of risks and disadvantages.  First, it is important to understand and have an overall management plan for the two crops before initiating this type of practice change.  It may seem logical to simply manage the two crops as you would if you were growing them separately, but this could lead to crop failure.  The overall nutrition requirements of both crops should be considered, as well as fate of nutrients put on fields with continuous roots.  Likewise, a herbicide plan needs to take into consideration the residual effect on the relay crop.  In addition, having plants and roots in the field can harbor insects and diseases that one might not get if there was a clean break between the two crops.  These are all things that can be managed if planned for and actively scouted.  Another disadvantage is that planting and harvesting can be more difficult when dealing with another crop in the field.  Both of these could take longer due to the field biomass and could require a purchase of special machinery to make relay cropping work.  This same concept applies for termination of crop instead of harvest.  Depending on the type of termination chosen, new equipment will likely need to be purchased.  And finally, relay cropping can be more labor intensive, and require more skilled labor, which is hard to find, than growing the two crops separately.³
 
Key Take Aways…         
While the goal of relay cropping is to make more profit on two crops grown together rather than the two grown separately while improving soil health, this is not always the case.  Relay cropping takes some practice and experimentation to figure out when and how to plant, manage and harvest, and it can vary from farm to farm.  As with all new practices, it is best to start off small and grow as you learn.  Relay cropping can be a practice change that helps improve soil health and increase carbon sequestration, potentially qualifying you for future carbon market programs. If you are interested in learning more about Truterra’s carbon market access program or carbon program, visit www.truterraag.com/carbon.