Cover crops assist efforts in sustainable agriculture
by Jena Trolio
Editor’s Note: This article is a product of a student in Nutrition 430 at Penn State. Voices is proud to present this work as a fulfillment of the community service aspect of that course.
If the majority of the world continues to farm using the methods currently employed, before long, the land will become so degraded that it will be rendered useless for food production. The chemical-based, industrialized agricultural systems that are seen feeding most of the globe are causing very serious environmental problems; namely, these methods are destroying soil quality by rapidly depleting levels of organic matter and producing greenhouse gases that are heavily contributing to climate change. The countries bearing a significant amount of the brunt from these unsustainable farming methods are those in Sub-Saharan Africa, the ones who are already in the most desperate of food situations.
Chemicals and industrial farming are not the answer to the food shortages experienced there. In order to begin producing food sustainably, we must employ worldwide a remarkable and under acknowledged solution – the use of cover crops.
The reliance on chemical fertilizers to grow food is stripping our soil of its organic matter. The organic matter of soil provides the most nutrients to crops. Present mistreatment of the soil through excess chemicals and plowing is ruining it for the future, making it impossible to continue reaching the crop yields attained today. Producing these chemical treatments also requires the burning of tons of fossil fuels in high-energy processes, stimulating climate change. These farming processes are doing far too much harm to the Earth, and Sub-Saharan Africa is trying desperately to produce enough food to ward off starvation with their depleting resources.
In Sub-Saharan Africa, climate change is causing extreme precipitation events and horrible droughts that are impossible to predict. On top of the issues of water shortage, the soil there is so depleted of organic matter that people fear the soil quality can never be recovered if things continue along this path. It’s become a cycle of degradation – the soil is deprived of organic matter and cannot produce as much food, so farmers plant more seed and place even more stress on the soil. Depletion of the natural resources in Sub-Saharan Africa makes shortages even more severe and permanent than what is currently happening very possible.
So what can be done to counter-act years of unsustainable farming? One answer lies in something being researched at Penn State – cover crops. I work as an undergraduate research assistant in a soils lab in the College of Agricultural Sciences, and there is some incredible information being gained on all the benefits cover crops can provide.
Cover crops, also known in systems as “simultaneous fallows,” incorporate the growth of plants that will add nutrients to the soil alongside the crops being grown for subsistence and income. As the plants die, their leaves fall and decompose on the soil, allowing the nutrients to rebuild the organic matter content. Increased organic matter in soil provides more nutrients for plant uptake, higher water holding capacity, and more biodiversity of microbial and insect life within the soil. Not only will cover crop installation repair the soil and reduce climate change emissions, but it will also naturally reduce weeds in the farmland. Weed picking is typically known as women’s work in Sub-Saharan Africa; if the presence of weeds drastically decreases, the women have more freedom to spend their time doing other things.
Such a simple solution has incredible benefits on the environment, and the crops themselves all have very different functions. For example, rye is commonly used as soil cover to prevent erosion. Mixing cover crops can be useful, as well, when done correctly; this is one of the main things being studied in the soils lab I work in. Legumes that perish in the winter are grown with legumes that are winter-hearty in order to keep the soil constantly supplied with higher nitrogen levels, reducing the need for a chemical fertilizer. Legume cover crops can supply 75 to 125 pounds of nitrogen per acre if they are well taken care of. Another popular combination is that of a grass and a legume. This mixture provides the soil with nitrogen through the nitrogen-fixing legumes and also with high buildup of organic matter from the high biomass of the grasses.
In time, if we continue to farm in the industrial and chemical-based way that we do today, the world will be left without any soil viable for food production. Some of the world’s poorest countries, those in Sub-Saharan Africa, are already being forced to face this harsh reality. Their unpredictable precipitation schedules and severely degraded soils are leaving the people of Sub-Saharan Africa desperate for an alternative to the farming they have gro