“As spring temperatures go up, it’s an excellent time for farmers and gardeners to focus their attention down to the soil below them. A spring check-up of your soil’s health gives clues of your ground’s ability to feed plants, hold water, capture carbon and more,” says Alice Begin, Resource Conservationist with USDA’s Natural Resources Conservation Service (NRCS) in Maine. No fancy equipment is required. Just grab a spade or shovel and prepare your senses to dig a little and learn a lot.
It doesn’t matter what kind of landowner you are; small farmers, large farmers, organic farmers and even home gardeners can all benefit from this simple discovery project of one of their most important resources. And in the process you can reap big rewards for your crops and the environment around you.
With your shovel, nose, eyes and hands ready, Begin suggests the following steps to investigate soil health:
• LOOK – first at the soil surface which should be covered with plant residue, providing organic matter and preventing erosion. Dig into the soil and observe the color and structure. It should be dark, crumbly, and porous—rather like chocolate cake. Healthy soil is full of air holes and live roots, and of course, you should see earthworms—our wonderful soil engineers! Poorer soils are lighter in color, compacted or unstructured, and lack living roots and critters.
• SMELL – Healthy soil should have a sweet earthy smell, indicating the presence of geosmin, a byproduct of soil microbes called actinomycetes. These microbes decompose the tough plant and animal residues in and on the soil and bring nitrogen from the air into the soil to feed plants. An unhealthy, out-of-balance soil smells sour or metallic, or like kitchen cleanser.
• TOUCH – Soil should be loose and crumble easily indicating a porous texture. This holds water better making it available for plants and stemming flooding and runoff. In healthy soil, roots can grow straight and deep, allowing plants to reach nutrients and water they need to produce the food we love to eat.
Maine is fortunate to have productive soils. It is up to gardeners, landowners, and land managers to preserve and even build their productive capacity. Basic principles to improve or maintain soil health apply to small gardens, large agricultural fields, and even pastures. They include:
• Minimize soil disturbance. The less a soil is tilled, and the more shallowly it is tilled, the better the all-important organisms in the soil do. Many farmers and gardeners are turning to reduced tillage and no-till systems to save energy and improve soil health.
• Reduce or eliminate bare soil. In nature, healthy soil is covered by something, be it living plants or dead organic matter. Bare soil erodes easily. Rainfall runs off bare soil rather than sinking in. And bare soil temperatures can rise high enough to be detrimental or even deadly to soil organisms. Utilize cover crops and mulches in gardens and fields where crops are grown. If you have livestock, manage grazing with rotations to allow grasses and clovers to regrow before being re-grazed. Maintain a minimum height of 3-4 inches on pasture at all times.
In addition to the vital production values of soil health to the individual farmer or gardener, Begin explains that healthy soil has clear impacts on many of the larger agricultural and environmental issues of our day, from sustainable food production to water quality to mitigating climate change. Healthy soil holds, filters and regulates water, mitigates drought and flooding, reduces runoff and erosion, cycles nutrients, sequesters carbon and suppresses weeds and pests. For all these reasons NRCS has recently launched a nationwide effort to “Unlock the Secrets of the Soil.”
Not sure your soil passes the sniff-feel-see test? Visit the Soil Health website at http://www.nrcs.usda.gov/wps/portal/nrcs/main/national/soils/health/.