Farming is not
a natural act, at least from the wildlife ecosystem perspective.
Yet agriculture done well fits each landscape, thanks to the
farmer’s careful understanding of what the land needs.
Two elegant tools for the regenerative farmer are crop rotation
and cover crops. Crop rotation is selecting a sequence of
crops for a field that improves soil quality while it sustains
the farmer. Cover crops are plant species grown primarily
to benefit the soil or other crops, while they may be harvested
as well for seed or forage.
These tools each encompass a set of management practices
that range from rudimentary to infinitely complex. They both
seek to optimize production of crops in ways that are best
suited to the land. Variables to consider include soil type,
weather patterns, soil slope, organic matter status and goals,
soil fertility, soil health indicators, crop pest pressure,
surrounding crops, economic goals, previous and coming crops,
soil management history and livestock interaction.
Conventional farmers in 2002 who sell commodity crops have
little economic incentive to rotate crops or use cover crops
unless their practices are so degrading to the soil that they
can’t afford to pour on more fertility than they are
hauling off.
The biological and ecological costs of planting monoculture
(single species) farmscapes of one or two crops are significant,
however, in the areas of soil health and water quality.
By adopting a crop sequence – season to season, year
to year – ideally suited to a field, a farmer builds
up the soil while producing valuable crops. Crops vary in
their demands from, and contributions to, agricultural soil.
Demanding that the land produce high yields every season leads
to depletion of soil quality unless the soil is improved.
Cover crops greatly expand a farmer’s ability to maintain
soil quality and fertility. Legume crops fix nitrogen from
the atmosphere, while grass crops create heavy root biomass.
Winter annual crops protect soil when photosynthesis is shut
down or minimal, and provide strong regrowth in early spring.
Quick-germinating grains provide a “nurse crop”
for slow-germinating perennial hay crops such as alfalfa and
clover.
These two tool sets are building blocks for regenerative
farming systems the world over. They are required for most
certified organic plans. They create the farms instantly recognizable
as having biodiversity that favors an abundance of life forms
while providing other “ecosystem benefits” that
we are still learning to appreciate.
When they are used in tandem, crop rotations using cover
crops:
- Decrease pest pressure from insects, weeds and diseases.
- Enhance biological activity in the root zone to improve
nutrient transfer from soil to plants and expand root growth.
- Improve soil physical condition through increased organic
matter that absorbs water better, holds more moisture into
dry times, drains better in wet times and creates better
earth worm habitat in all times.
- Create biologically and economically durable crop systems.
NewFarm.Org will bring you many applications of covers and
rotations across the continent and around the world. Many
examples will be at the farmer-to-farm level. We’ll
bring you the best work, recommendations and images from leading
cover crop research sites when they are practical and inspiring
for farm use. And we'll be featuring an ongoing series of
accessible and easy-to-understand views of crop rotations.
We'll look at crop rotations that provide specific benefits--managing
pests or building soil quality and health. We'll look at length
of rotation and provide varied examples of 2, 3, 4, 5 and
7 year rotations. We'll look at rotations that fit well with
specific cash crops or crop mixes. And, of course, we'll provide
information on regional variations and issues wherever possible.
The excerpts listed below, co-authored by NewFarm.Org editor
Greg Bowman for the Sustainable Agriculture Network, give
a whirlwind tour of suggested rotations in two kinds of systems,
then a close look of how they work on one exemplary farm.
If these ideas are new to you, just look for the principles
involved. If you are ready for multiple cover crops, study
the details to where you can pick up some pointers.
- Page
2:
Crop rotation with cover crops: an overview
- Page
3: Full-Year Covers Tackle Tough Weeds: a profile
of a PA farm
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