The Pros and Cons of Cover Crops

For centuries, farmers have been seeding their hay and pasture lands with cover crop. There are many benefits to seeding cover crops, but there can also be financial downsides. Let’s explore the pros and cons of the cover crop system.

Cover crops are often grown for the important purpose of preventing soil from eroding. A very dense layer of cover crops can literally decrease the speed of rainfall before it even hits the ground, lessening surface runoff and causing the soil not to splash. The abundant root networks of cover crops keep soil firmly in place, providing the perfect habitat for macrofauna to thrive. Also, in the process of reducing soil erosion, cover crops work as barriers to excess water, which poses an environmental threat to ecosystems downstream. By helping the soil absorb and retain water, cover crops diminish the amount/rate of water that would normally trickle off into other areas and thus keep rainwater from besetting the surrounding countryside.

Cover crops also help increase soil’s fertility. Certain kinds of cover crops, “green manure,” help manage soil nutrients and can play a valuable part in regulating soil makeup. This is the main reason cover crops are used: instead of serving as food for harvest like most crops, cover crops are never gathered but are tilled back into the soil when their growing cycle reaches its end. In the decomposition process, nutrients are released into the soil, serving as a kind of makeshift manure or compost without requiring a farmer to waste time hauling manure. Legumes, for instance, are known to convert nitrogen found in the atmosphere into a soluble form absorbable by plants in the field. Other types of cover crops accumulate vital nutrients such as phosphorus that can tremendously benefit the quality of the soil. No matter what, all cover crops infuse organic matter into the soil.

In addition, the practice has proven to be an ideal way to combat the infestation of weeds. As a competitor for nutrients, space, etc., cover crops hinder the growth of germinated weed seeds and inhibit weeds from propagating. Sometimes cover crops do not function as manure and are left on the surface after their life cycle ends, forming an almost impermeable layer above the soil that blocks weeds from getting the light they require to grow. Even after death, cover crops are able to create a mat of mulch that smothers any fresh batches of weeds from rising out of the ground.

There are a few other surprising benefits of cover crops, including pest management, improvement of wildlife habitat, control over the spread of fungal and bacterial disease, and plant diversification, but that doesn’t mean cover crops are a surefire benefit. On the one hand, they have tremendous possible advantages, as we have seen, but, on the other hand, there’s no official guarantee that they will be productive and helpful. Many farmers find it difficult to calculate a specific monetary value for cover crops and be convinced that they will get a good return on the investment, making seeding these crops seem like an imprudent decision in the long run. Especially in tight financial times, it’s easy for a farmer to be dissuaded from emptying his/her pockets and going out of the way for something that appears like more of a luxury than a verified necessity. In addition, the use of herbicides and seeding directly even minimizes the reliance on cover crops. Some experts advise that if you don’t absolutely feel the need for seeding cover crops, then opt out because they wouldn’t be worth the extra hassle and expense. There are always uncertainties in farming: in the end, it all depends on assessing the state of a farmer’s equipment and fields to determine whether it’s worth the leap of faith and if the benefits of cover crops outweigh the risks.