Written by Katherine Favor, Vineyard Coordinator at Coastal Roots Farm
Here at Coastal Roots Farm’s Food Forest, we employ many different agroforestry practices. Agroforestry is the practice of combining trees with agriculture, and it has amazing benefits such as increasing farm yields, conserving soil and water, limiting the use of pesticides, increasing wildlife habitat, and even sequestering carbon from the air to fight global warming. There are dozens of different agroforestry practices, but at the Farm we utilize a few in particular: food forestry, silvopasture, wildlife corridors, and alley cropping. There are so many reasons why agroforestry is great, but today we’re going to deep-dive into the benefits of a silvopasture system.
Silvopasture is a popular agroforestry practice combining trees, forage, and livestock into a single integrated practice. Silvopasture consists of rows of trees with forage grown underneath that is grazed by animals. There are three elements to silvopasture: trees, forage, and animals. When these three elements are managed and integrated in a mutualistic way, silvopasture has the potential to benefit the environment in many ways. It improves soil and water quality, reduces the incidence of animal disease, allows us to not use chemical fertilizers and herbicides, increases wildlife habitat, and even sequesters carbon, helping to fight climate change. As with any agricultural practice, there are challenges and limitations to silvopasture agroforestry, but when the system’s tree, forage, and animal elements are integrated in a balanced way, it has huge promise for both organic farms and our planet as a whole.
First, let’s talk about the trees. In a silvopasture system, tree varieties must be selected carefully. In our silvopasture system, we have selected cape wattle trees and elderberries, along with a mix of fruit trees. The cape wattle trees act as what we would call “fertilizer trees” by fixing nitrogen. That is, their roots have a bacteria in them that actually take nitrogen from the air and turns it into a solid form that plants can absorb. It’s magic! Our elderberries provide a large amount of biomass for mulching, which also adds back nutrients to the soil and creates a carbon-rich habitat that beneficial fungi really like. All of the trees we’ve selected are drought tolerant so that we aren’t forced to over-irrigate, and they are also deep rooted so that they don’t compete with the forage that we grow. All of the trees draw nutrients up from deep in the soil and bring them to the soil surface. And all of the trees that we grow produce light shade so that forage can still receive some light and grow well underneath them. Our fruit trees, of course, have the function of producing delicious fruit for us to eat. We’re currently growing pomegranates, sapotes, and figs, but we’re going to be planting many more varieties. Right now we’re following the Jewish law of orlah and we’re waiting for them to grow strong before we harvest from them, but in a few years we’ll be able to eat them.
The animal element of a silvopasture system must also be managed with great care. Not every animal is the right match for a silvopasture system; the variety of animal must be compatible with both the variety of forage, the variety of trees in the system, and the overall goals for the system. Cattle, sheep, goats, and poultry all can be utilized in silvopasture, but at the Farm, we choose to rotate only chickens. This year we’ll be increasing our flock, whose eggs will be sold at our Pay-What-You-Can Farm Stand. The way that we rotate our chickens is important, too. Our chickens do not continuously graze but are instead rotationally grazed in what is called a “management intensive grazing system.” This means they are moved between many different parts of the silvopasture throughout the season, which allows each pasture to get a period of rest before being grazed again. Come to the Farm and you’ll notice that our “chicken tractor” is in a new spot every week. It is moved often so that our chickens are constantly in a new spot. They eat forage (which gives those eggs that beautiful orange color) and they also simultaneously fertilize the ground with their excrement. They act as both our weed control and our fertilizer, and they produce delicious eggs because of it.
We also modify what kind of forage we sow in our silvopasture year to year depending on what our soil and chickens need. This year, our goals are to get more microbes and nitrogen into the soil, to build more organic matter, to keep moisture in the soil, and to smother out weeds. To do this, this year we’ve selected four cover crop varieties: nitro radish, black oat, yellow clover, and common vetch. The nitro radishes add a lot of sugary exudates (plant sugars) that microbes love. The black oat smothers out weeds and sequesters a lot of carbon from the atmosphere. It also has a mat of roots that can add a lot of organic matter to the soil very quickly. The yellow clover adds nitrogen to the soil. And the common vetch also adds nitrogen to the soil, while simultaneously covering a lot of ground and keeping moisture in the soil. The chickens love to eat nitro radish and vetch, so they’ll get a lot of nutrients from this cover crop, too.
When designed correctly, silvopasture systems have the potential to create balance between trees, forages, and animal systems, all while improving soil, providing wildlife habitat, and fighting global warming by sequestering carbon. Our silvopasture system is still young and developing, but we are so excited that, as the years go by, we will be able to produce a large amount of food from it, all while healing the planet. We’re proud of the way that we’re farming!