CONCEPTIONS Beef Cow-calf newsletter Jan-Feb 2023
A recent
(January 2023) article in Stockman Grass Farmer carries an
article by Mississippi beef, pork and poultry rancher Ben Simmons entitled
“Biology supersedes Chemistry.”
His lead paragraph says “You can have mineral nutrition perfectly balanced on a
soil analysis and yet will not grow healthy plants on that soil, as long as you
have poor biology.”
Soil biology is essentially three forms.
We are all familiar with worms; nematodes and dung beetles perform
related recycling functions. There are
also bacteria and fungi. The optimal
proportion of bacteria to fungi is 1 to 1.
These soil biology forms transport nutrients into the growing plant
roots.
Compacted soils have little effect on bacteria (which are anerobic) but can
seriously harm the fungi (which are aerobic, ie, they need oxygen) as well as
worms and nematodes. The better soil
will have “structure” (air pockets and water infiltration channels) which is
built up by root masses (alive and growing or dead and decomposing) and
incorporated manure and crop fiber residues.
These are called “high organic matter” soils which capture rain, whereas
a tighter, compacted soil (even if the surface is tilled) will allow rain to
runoff, often eroding topsoil with it as it flows into your drains and out to
streams.
While chemical fertilization and weed suppression generally insures us a crop
harvest, these practices can inhibit soil biology and thus lower the residual
fertility of your soil. Over history
the use of chemical herbicides and pesticides has grown in tandem with
longer-maturity crop varieties, leaving no time for the planting of “green
manure” cover crops. Leaving harvested
fields bare of growth over the winter can starve and even freeze soil biology
of all forms, while free carbon breathes out from the soil and enters the
atmosphere. (Ten times as much green
house gases are released by open soils as are produced by all our ruminant
livestock!) If we analyze crops grown
on soil treated this way, you find the nutrient density to be lower as our
yields have gotten greater.
When you hear that term “empty calories” being applied to our modern grain
production, the key ingredient in most processed consumer foods, the losses of
soil biology are the most direct explanation; plants lack the nutrients they
bring to the root zone, especially from fungi. (Both animal and human health suffered from
monocultural crop production dependent on chemical fertilization and
propogation. Look at how the “Covid”
situation drags on!)
What
our animals can contribute to improved soil biology and resulting fertility
Because you have
animals, some of your land benefits from incorporation of their manures. However, to get the “whole enchilada” of
soil stimulation and health from animals, you need to graze every field at some
time of the year; not just manure, but
urine, enzymes, nasal drizzles, even shedded hair, pass microscopic bacteriology
onto (and if not compacted, into) the soil and contribute humic substances that
stimulate the growth of mychorrizal fungi.
Short periods of intense grazing (spring cool-season green vegetation,
or fall planted covers including some that regrow in spring) can provide some
cheap feed for your animals at times when the soil is most receptive to animal
effluents. These same fall and spring
covers keep root masses growing in winter, thus helping to keep soil bacteria
and “companion livestock” alive. In
some synergistic way, the animals’ total biological exchange aids soil health. All that is required are permanent corner
posts and temporary fence you can roll out and retract between crop growing
seasons.
Mob grazing large numbers of animals on degraded soils in places like Africa
and the USA deep south where monocultural cotton and tobacco depleted soil
fertility, has proven able to bring those acreages “back to life” able to
support desired plant growth, sequester carbon, and most importantly, capture
rainfall into the root zone. ( Refer to
Allan Savory, whose Holistic Resource Management has guided noted
USA cattlemen like Greg Judy to increased cattle production.)
Soil compaction occurs in many ways:
from driving across wet soils in cool seasons; from over- application of anhydrous; from deep plowing that turns furrows
completely over, burying any green growth or crop residue into an anerobic
layer that does not decompose; from
hard rains onto barren or tilled ground, promoting runoff; from continual growing of row crops that
leave large bare spaces between rows subject to evaporation and excessive
warming from the sun; from not growing a cover crop in the winter to replace
organic structure consumed by each row crop.
As for pastures, the overgrazing of the more desired species by “set grazing”
(instead of regular rotation of paddocks to prevent chewing the green growth
below a 4” to 6” height that insures photosynthesis for regrowth) not only will
degrade the pasture plant mix (opening up space for weeds to enter) but also
leads to compaction from the warming of the soil similar to the effect in row
crops. Studies prove that your animals
can harvest 50% more plant growth across the grazing season if paddock divisions
are established and frequently rotated.
It used to be common to see beef cows gleaning the wasted corn and residue
stalks after corn harvest. Combining
usually leaves 2 bushels or more per acre on the field surface. Even if all you do is roll round baled hay
out across crop residues for winter feeding, you will note greener color under
the path of the bales the following spring, and a healthier crop that
summer. Let your animals work
harder for you. It will save you $$ and
increase both calf and crop yields.
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