Cover Cropping, Clarified
The economics of implementing cover crops in different farming systems helps to explain the wide range in adoption rates by sector.
All the hype and money in cover cropping these days has brought a bunch of messaging into agriculture that means different things to different farms. This report explores the specific activities, limitations, expense and revenue outcomes for adding cover crops into each distinct production system.
Fresh Produce
Cover cropping between rows of grapevines, berries, vegetables, etc. is fairly straightforward because the rows in between are already wide enough for small equipment. Seeding and termination of cover crops are physically separate field activities from the work of growing fresh produce, and each can be mechanically managed using purpose-designed operations and equipment.
The alternative is tillage and bare soil between rows, which can lead to nutrient leaching and erosion. The water holding properties of the soil are improved by the cover crops, and on some farms, they can be grazed by livestock adding natural nutrients and additional revenue.
Intercropping = Cover Cropping
Commercial grain farms are managed using equipment designed for producing a single crop across a large space. Incorporating additional species complicates field preparation and production activities, which is why broadacre grain farmers most often produce two commercial crops together with the intention of marketing both.
Sources in agroecology report that soil health improvements from plant diversity accelerate when about 8 different species are present. However, farmers report that they already observe improvements in the first season of growing just 2 different crops on a field.
Common intercrops include pea-canola, lentil-oat, and chickpea-flax. Despite differences in days to maturity, it generally works to seed and harvest them both together.
Sometimes seed expenses are higher because plant density is part of the strategy for weed control in an intercrop. The expense savings start with most in-crop herbicide passes compared to the applications on neighboring monocrops.
Savings come in fertilizer as well, as legumes naturally feed the companion crop nitrogen through atmospheric fixation during the growing season. Fungicide and insecticide requirements fall too, because the more complex intercrop is a less welcoming environment for disease spores and insects.
By far the biggest hassle with intercrops is separating and marketing them. It can take a long time to get this job done on the farm, using augers and small cleaners, and it is essential that it be done well before marketing the crops to elevators.
Coming Soon! Prairie Routes is developing a new grain brokerage service exclusively for intercrops. We will take on the job of lining up cleaning, transportation, documentation and contract management, and work with buyers on market development and segregation. For more information email hello@prairieroutes.ca.
Seeding an Understory
Cover cropping on grain farms can also mean planting an understory such as red clover with corn or wheat, that is only there for building soil health, not to be harvested. The soil health benefits are similar with this type of cover cropping, but the economics aren’t as favorable as intercrops for a few reasons.
Cover crop seed is in short supply with all the funding programs available, making it expensive.
The economic gains come in future years’ reduced fertilizer and pesticide requirements, which are difficult to forecast, measure, and accrue against the up-front cost of seed.
Depending on growing conditions, cover crops can be thick and green at the time of harvest. Combines weren’t designed to handle thick plant matter along with dry grain crops and understory cover crops make them prone to plugging up.
When we build Business Plans for Fields with commercial farmers in the Northern Plains region of North America, cover crops alone are rarely contemplated, mostly because the window is too short for post-harvest establishment. There are also too few clear examples that seeding understories on commercial grain fields – especially compared to intercropping – represents a reliable pathway to long-term economic sustainability.
Cover Cropping on Ranches
Dictated by entirely different economic considerations, the term ‘cover cropping’ on a ranch refers to the feedstock purchased to raise livestock. Rather than offering troughs of feedgrains or corn silage to penned animals, ranchers manage livestock across pastures seeded to multi-species cover crop blends designed to optimize nutritional value and growing days in their region.
The same benefits accrue to the health of the soil - and then some - because the animals contribute natural fertility and termination of the pasture. In future years, crops can be produced with significantly lower crop inputs on previously-grazed fields.