Maine – April 16, 2013 -- “As spring
temperatures go up, it’s an excellent time for farmers and gardeners to
focus their attention down to the soil below them,” says Alice Begin,
Resource Conservationist with USDA’s Natural Resources
Conservation Service (NRCS) in Maine. “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.” 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.”
