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Severe wind erosion of a recently planted no-till milo field. Lik e they say,
there's good points and bad points about everything. And no till is no
different.
But in years like
this when nature provides a severe stress test, the myth rapidly fades
away--that no till is the perfect way to farm. A friend of mine who is heavily
into no till once observed that when you go to no till, you simply trade one set
of problems for another. And this year, we're getting to see the dark side of
no till.
Back in the early
'70s, I remember conversations with USDA researchers at the Akron Experiment
Station in northeast Colorado. At that time, they had already started
benchmark studies with various no till programs and rotations.
But even then they
periodically complained about the soil turning hard as a rock in dry years.
Today, 30 and 40 years later, the ground still gets hard. And we still don't
have a solution to the problem.
The adobe seedbed is
not to be taken lightly. It's hard to believe but the most severe wind erosion
of the past 5 years has been on no till land where farmers could not get wheat
stands. This year because of the severity and earliness of our current drought,
we saw many no till fields blowing as early as May. In large part, these were no
till milo fields.
Usually, though, the
no till wind erosion is most notable on fallowed land where farmers could not
get wheat stands in the fall. After baking all summer long and then setting up,
it's impossible to penetrate it with any kind of drill. Then, with poor or no
ground cover, the soil starts blowing in late winter.
In a recent
conversation with DeAnn Presley, KSU soils scientist, she said she knows exactly
what I'm talking about. "I have frequently seen this in not only western Kansas
but also in south central Kansas.
"And the reason why
it happens is because whenever no till soils have fairly low residue cover, they
can often have worse soil tilth than tilled soils. With low residue cover, the
soil surface isn't protected very well from raindrop impact. And then we get
crusts which are more prone to erosion. But if you till the soil, you break up
the crust," she says.
In the literature
from the '70s, soils scientists talked about tillage creating non erodible
aggregates. We call them clods. But whatever name you prefer, they protect the
soil from erosion. " In addition to
what's happening on top of the ground, significant changes can also occur under
the soil surface when things go bad with no till. Presley also says
it's not much of a stretch to call the hard no till seedbeds, "adobe
seedbeds". "To make earthen bricks, you'd use a non-expansive soil to which
you'd add in a mastic or straw to give it strength. "Bake it in the sun and
presto, you've got adobe."
After collecting
data on tillage practices in several Kansas counties, Presley said she was
confused by what farmers were doing. "The data showed most of the irrigated
wheat as being no till and most of the dryland wheat as being reduced till. I
thought that was backwards but after talking with some farmers, they kept saying
the soils get too hard to get wheat stands so they're doing some tillage on the
dryland fields.
"And I think that is
a good idea for two reasons. First, they can get the disc openers in the ground
and get a stand. And second, by putting a loose layer of soil on the surface, it
acts as a dust mulch to trap moisture below. The tillage pass not only cuts off
the weeds but also limits evaporation. Bottom line is that I would not despair
at all about doing some tillage," she says.
Complicating the
situatio  n is our current drought. As crop yields decline because of the dry
weather, crop residue production also drops. It is said that for every bushel of
wheat grain yield, you have 100 pounds per acre of stubble produced. So with
yields of 20 and 30 bushels per acre, there's just not a lot of stubble
generated to protect the ground. Stubble production with annual cropping is
probably even worse. Observers of the Dirty Thirties say the severe wind erosion
of the time was due to annual cropping in combination with inversion tillage.
Hopefully we've learned our lesson on the inversion tillage part of the
equation.
Also in looking at
research at the Tribune Experiment Station, as cropping frequency increases,
yields decline. When going from a wheat-sorghum-fallow rotation to a
wheat-sorghum-sorghum-fallow program, yields of the second sorghum crop decline
30%. Crop residue production also drops which leaves the soil vulnerable. At the
same time, frequency of crop failure sharply increases under the more intensive
rotation.
In summary, I've
often heard it said that a good farmer can make any system work. But I think
we'll all agree that any system works a lot better if it rains. So keep
praying! Vance Ehmke and his wife, Louise, farm in Lane County.
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Ag Blogs 
make us humble.
I enjoy reading your articles Vance, and the pictures tell the whole story.
I can add one to the drouth story. I worked a wheat stubble field for the first time,parked my 4-wheel tractor in the corner and that evening
the wind blew 86 mph with a gust clocked at 103 mph . It covered my 54’ sweep completely over with straw & dirt.
There were 22 pivots turned over in Thomas Co., a 500,000 bu. bin caved-in and many buildings damaged or destroyed in the county.
I’m praying for rain.
Much more reliable for first Americans and the rest of us to learn from in this kind of Kansas non-mono-culture. Inconvenient truth (i know)!
Considered becoming home builders? Might sell more adobe pueblos than wheat.
Gosh those photos are hideous. Rain! Go visit the Ehmkes!!