Rotations Build Soil, Control Pests, and
Keep Farming Interesting
Cris Carusi and Martin Kleinschmit
Tom Larson grins as he shows off the
Dragonfly, a sleek two passenger plane which he
built over the course of several winters.
Aviation is his hobby. His knack for
craftsmanship shows as he explains how he built
his plane from foam, fiberglass, and a Subaru
engine. The Dragonfly embodies Tom's conviction
that there is more to life than farming.
Tom approaches farming with a similar attitude
of craftsmanship. He rotates soybeans, corn, oats
with turnips and cattle through his ridge-till
strip-cropping system. He adapted most of his own
ridge-till equipment from used machinery. His
irrigated 160 acre St. Edward farm, which
includes 60 acres of row crops and 90 acres of
pasture and hay ground, has been in his family
for 61 years.
His grandfather and father raised monoculture
corn on the farm until the early 1970s. At that
time, a neighbor was experimenting with a
corn-soybean rotation, and achieving good
results. Tom liked what the beans did for the
soil, and he saw income potential in the soybean
crop. He and his dad decided to give rotations a
try. The corn-bean rotation provided the Larsons
with good returns and soil benefits. They
eventually added oats to the system, to gain
Tom now rotates his crops in 152-inch wide
strips (4x38"). Soybeans, the first crop in
this rotation, provide a number of benefits to
the system, including pest control, nitrogen for
the following year's corn crop, and cash.
Rotations prevent insect pest populations from
exploding. "Insects are creatures of
opportunity," Tom explains. "They will
build up in large populations where the
environment is right for them. If you keep
changing environments on them through rotations,
it has been my experience that they do not become
a large problem. Anyone who puts in corn after
soybeans really should question whether or not
they need a soil insecticide."
Corn is the second crop in the rotation. Tom
chose to keep corn in the system because of
convenience and tradition: "I wanted to
raise corn, because that's part of your identity
in this area. We're corn growers, and there's a
convenient market for it."
Tom has seen increased corn yields from his
system. With strips four rows wide, the entire
corn strip benefits from the "edge
effect". Under a conventional cropping
pattern, yields in the middle of the field can be
lower than around the edges, because of excessive
heat buildup and health problems. Tom believes
that his four row strips are an optimal size.
The third crop rotated into the system, oats,
is planted directly into the corn stubble the
following spring. The oats are harvested for
grain or straw, depending on the market.
Following oat harvest, Tom re-builds his ridges
and broadcasts turnips, to provide fall forage
for his cattle.
Crop rotations help control weeds, as tillage
operations happen at different times for the
various crops. Including oats in the system is
particularly valuable, because the mid-summer
harvest helps break weed cycles. Tom has had some
trouble with early weeds, like shepherd's purse,
but controls them with shredding. He believes
that weed control is the best argument in favor
of ridge-till planting and cultivation.
The oats have improved soil tilth, as their
root system builds soil structure. It took about
three years for him to observe improvements in
his soil, like an exploding earthworm population.
Once he had successfully interrupted weed and
insect cycles and improved his soil, Tom's next
concern was to provide winter feed for his
cattle. He has 60 head of cattle to feed through
the winter. Beginning in the fall, when the
pastures are dormant, he supports his cattle herd
by strip grazing the corn and bean residue, and
The turnips are the most profitable part of
his operation, as he can potentially graze 300
head of cattle per acre per day on this crop. Tom
figures that he gets 4-5 times more net income
per acre from his turnips than from corn. His
input costs for the turnips are minimal, and he
has no harvesting expenses. The animals do the
work for him.
In his lifetime, Tom has moved from a
conventional corn monoculture to this diversified
system. He quit applying herbicides 6 years ago,
and insecticides 10 years ago. He switched from
anhydrous to manure fertilizer last year. He is
in the process of certifying his fields organic.
In the future, he would like to provide extra
nitrogen by interseeding a legume into his corn
Tom's system provides him with many
quality-of-life benefits as well. Although the
system is more labor-intensive than conventional
farming, the work is spread out rather than
bunched into stressful "crunch
periods". Better scheduling leaves him more
free time in the day for other things, like his
plane. He has noticed more wildlife on his place,
which he appreciates.
His wife, Deb, works in town to support the
farm, as many farm women do these days. Tom's
efforts pay taxes and insurance, and his wife's
income keeps food on the table. Good quality of
life is more important to the Larsons than making
a lot of money. Says Tom, "I'm willing to
accept a lower standard of living for an improved
quality of life."
Much of Tom's inspiration comes from Chinese
and Japanese farming systems. He cites Farmers of
Forty Centuries by HF King and One-Straw
Revolution by Mansanobu Fukuoka as favorite
titles. He is impressed by how these cultures use
and re-use their own resources as much as
"Basically, do only what's
necessary," advises Tom. "Always look
at what you're doing and ask yourself, 'Why am I
disking? Why am I planting and harvesting in this
manner?' Constantly ask the question, 'Is this
absolutely necessary, and is there an easier,
cheaper way of doing it?'"
Tom prefers to farm from the neck up,
substituting management strategies for labor
whenever possible. "I think that we've given
away our ability to know our weeds and our soils.
Its gotten to the point where people don't farm
fields anymore. They farm farms."
"There's other things that I could do
that would be more financially rewarding,"
he adds. "I guess I enjoy the challenge, or
I wouldn't do it."