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Drainage keys agronomics for these Minnesota farmers


During his crop-consulting
career, Mark Bernard has heard farmers complain about the costs of all kinds of
inputs. Seed. Fertilizer. Machinery.

There’s the price of one
input, though, that never raises a peep among farmers.

“I’ve never heard farmers
complain that they put in too much tile,” says Bernard of New Richland,
Minnesota. “Without good drainage on our soils, all other practices take a

Tiling Unleashes

Tile drainage is a
cornerstone for Duncanson Growers, Mapleton, Minnesota. Farm partners include
Pat and Kristin Duncanson, brother Karl and wife Jackie, and the brothers’
mother, Mary.

The deep and black soils of
this area aren’t what European settlers found when they trekked to southern
Minnesota in the 1800s. “Our soils are old geologic lake beds, prairies and
swamps,” says Pat. “They are silty clay, some with little loam in them.”

These swampy soils masked
excellent farmland that emerged when settlers improved drainage. Some peat
soils the Duncansons farm consist of 10% to 15% organic matter. That’s off the
charts, as many Corn Belt soils top off at 4% to 5% organic matter or less.

This high amount enables
soils to hold water during drought. They also can provide 20 to 30 pounds of
nitrogen per percent of organic matter. High organic matter also protects
against erosion and ensures excellent soil structure.

There’s a catch, though.
Excess water that seasonally saturates these soils slows drainage and stifles
tillage and planting. That’s where drain tile comes in. It persistently drains
excess water from these soils, which creates a moist and warm seedbed that
spurs germination and early growth. It also helps ensure timely planting,
aiding the Duncansons in their goal of planting corn during the first week of
April. Well-drained soils also help ensure timely spraying and harvesting, too.

“You can do nothing to
control the weather,” says Pat. “But tile that removes excess water helps
yields more than anything around here.”

Most of the Duncansons’
fields are pattern tiled. “In some cases, we take it to the extremes,” Pat says. “In
some fields we have 30-foot tile lines; other fields have 40-foot lines.”

Increasing tile drainage has
perked the recent interest of many other Corn Belt farmers.“When people started
yield mapping their farms, they were able to put a dollar value on the costs of
poor drainage,” says Bruce Erickson, a Purdue University agricultural

Equipment Keys Timeliness


Equipment selection also
enhances timeliness of field operations.

“You look around here and
you see we just have a few pieces of machinery,” says Pat. “The planter is the
most important piece of machinery we have. But we drive old pickups.”

If all goes well, their
48-row planter with 20-inch spacings can plant up to 500 acres per day.

“There is such a thing as
having too big machinery,” says Pat. “But in southern Minnesota, we have a
seven-day window on average to plant corn. We probably are oversized with a
48-row planter. But in some years, especially wet springs, it pays to have that
extra capacity.”

Mechanically sound tractors
also enhance timeliness.

“At planting, we don’t want
to fool around with a broken hydraulic line,” says Pat. “With a seven-day
window to plant corn, machines have to run. In the fall, we come in with a disk
ripper to take care of cornstalks. So it’s critical that everything runs right
for fall fieldwork, too. We upgrade our tractors regularly.”

This capacity enables the
Duncansons to be patient during planting, a point echoed by their planter
consultant, Kevin Kimberly, Maxwell, Iowa.

“He advises us to wait until
conditions are fit to plant,” says Pat. “It’s hard to wait, especially when our
neighbors are planting.” Waiting an extra day to plant, though, can reduce
sidewall compaction in wet soils.

“The worst-case scenario is
planting in wet weather and then having it turn dry,” says Pat. “We can have
sidewall compaction, where the seed furrows won’t completely close.”

An in-cab monitor a
automatically adjusts planter downpressure. “Too much downpressure can lead to
sidewall compaction,” says Pat. “Too little downpressure is not good either.”

Optimum downpressure changes
between soil type, fields, and even daily weather. “Good weather can cover up
some planter errors, but we do what we can to reduce our dependence on ideal
weather,” says Pat.

Once planted, liquid 10-34-0
starter fertilizer gives young seedlings the nutrients they need during early

Narrow-Row Perks and Pans

The Duncansons have planted
on 20-inch rows since 2006. Before that, they planted corn in 15-inch rows.


Narrow-row perks include
equidistant spacing that allows plants to garner more sunlight and boost
photosynthesis. Narrow rows also help blitz competing weeds due to early

In University of Minnesota
trials, 20-inch-row corn has outyielded 30-inch- row corn by 7% to 9%. Yield
increases with narrow rows have not always occurred in these trials, however.


Narrow rows also complicate
planting by moving residue into a smaller area. “We have to have some
aggressive row cleaners, but there is such a thing as getting too aggressive,
too,” says Pat. “The residue can spill into other rows and clog rows by
dragging and plugging.”

That’s particularly true for
corn-on-corn, which make up around 40% of their corn acres. “Corn-on-corn is
not as forgiving as corn-on-soybeans,” says Pat. “More residue complicates
planting. It takes more nitrogen. If we make a small mistake, corn-on-corn can
magnify it.”

Switching to 30-inch rows
would boost residue flow within planter rows. Thirty-inch rows also create more
combine options. “Twenty-inch equipment is more specialized and harder to
trade,” says Pat.

For now, the Duncansons will
stick to 20-inch rows, although they may reconsider when it’s time to switch
planters. “We revisit this every year,” he says.  

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