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SOIL HEALTH IN PRACTICE - REAL SOLUTIONS FROM REAL FARMERS

Cover Crops - The New “Weed And Feed”

Lessons From Organic Farmers That We Can All Learn From Photos by Dan Desutter

Only a small percentage of our customers are certified
organic, and for a good reason: it isn’t easy. The two pri-
mary challenges are weed control and providing mineral
fertility. True, there are ways to control weeds (manual
pulling) and ways to provide soil fertility (blood meal for
nitrogen, bone meal for phosphorus, greensand dust for
potassium), but the problem is that these methods are
also incredibly expensive and often not practical at scale.
Another drawback is that many organic farmers rely on
tillage as a means of weed control, and we all know how After corn harvest, a cover crop mix based around cereal
destructive tillage is to soil quality. rye is used to sequester left over nitrogen, creating an en-
vironment that is low in plant available nitrogen. The soy-
However, we know of some innovative organic farmers beans are planted into the standing rye which is then roller
who are developing means to control weeds without till- crimped at V2.
age or herbicides and providing nitrogen fertility with- Both corn and soybeans are planted in 30-inch rows, so if
out expensive purchased organic fertilizers. The key to any follow up weed control is needed it can be provided by
both practices is the intelligent use of cover crops. One of one of two methods. The first is the use of a “row-mow” –
these innovators is Dan Desutter of Attica, IN, who was a a device similar to a row-crop cultivator, but with the cul-
long time no-till farmer and cover cropper who decided tivator shovels replaced with a rotary mowing device that
to jump into organic farming. His experience with using cuts any weeds off just above the soil surface and turns the
cover crops to control weeds and fix nitrogen gave him the weeds into a nitrogen-releasing mulch. The second option
confidence that he could successfully make the jump to used to control weeds that grow above the soybeans is an
organic crop production. electric weed zapper. This device uses high voltage electric

Dan extended his rotation beyond the typical corn-soy- terminals that are mounted on either side of the crop row
bean rotation in his area to include wheat. Following and immediately above the crop. Any weeds that are poking
wheat harvest, a multispecies cover crop mix that includes above the crop complete the circuit between the positive
summer annual legumes like sunn hemp and cowpeas is and negative terminals and are literally fried. Not only is
planted for livestock grazing. After grazing, a winter mix this an effective weed control method, it is also great enter-
is planted that includes some species that winter kill, along tainment! Dan says that his corn grown in the cover crop
with a legume that overwinters, such as FIXatioN balan- mulch and all the decaying organic matter from previous
sa clover. This winter legume is then terminated with a crops and cover crops is healthier and more vibrant than his
roller crimper in late May, and the resulting thick mulch corn crops in the past.
provides a barrier to weed seedling emergence as well as a
slow release nitrogen source.

In late May of 2019, Dan measured the nitrogen content of
his balansa clover mulch and found it contained a whop-
ping 350 pounds of total nitrogen! Even when figuring
that only half of this nitrogen might be available to the
following crop (soil microbes always sit at the table first,
plants get the table scraps) this amount can fulfill the ni-
trogen needs of a very high yielding corn crop, especially
when combined with the nitrogen produced by the decay
of the previous summers cover crop and the manure and
urine left over from the grazing.

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