Dr. Hans Kandel, Regional Extension Educator, Crookston Regional Extension Center,

Changing Cropping Practices in Response to Challenging Weather
Dr. Hans Kandel, Regional Extension Educator, Crookston Regional Extension Center,
251 Owen Hall, 2900 University Avenue, Crookston, MN 56716-5001.
Email: [email protected]
Climate data shows that there have been major changes in NW Minnesota weather patterns. There are
warmer winters, higher minimum temperatures (especially in the winter), higher dew points, and more
precipitation than previously recorded.
The normal rainfall (based on a thirty-year period) has increased 16% since the 1921-1950 period, in Ada,
MN. Increased heavy rainfall during the growing seasons is challenging in crop production systems. As
weather patterns have changed so have the crops grown in NW MN.
Trends in crops grown in Minnesota District 10 (Kittson, Roseau, Marshall, Polk, Pennington, Red Lake,
Norman, Mahnomen, Clearwater, Clay and Becker counties) show that in 1965 oat, wheat, and barley
with 30, 19, and 14% of the harvested acres, respectively, were the dominant crops. In the same region in
2006, wheat and soybean with 37 and 30%, respectively, of the harvested acres, are the major crops.
Harvested Acreage
Potato
2% Canola
Sunflowe r
0%
Flax
0%
5%
Edible be an
0%
Sugar be e t
3%
Whe at
19%
Flax
0%
(District #10)
Barle y
14%
Harvested Acreage
Potato
0%
Canola in 2006
1% (District #10)
Sugar be e t
8%
Soybe an
30%
Soybe an
4%
All othe r
hay
8%
Alfalfa hay
12%
Corn silage
1% Corn grain
4%
in 1965
Dry be an
2%
Sunflowe r
3%
O at
30%
All othe r
hay
Alfalfa hay
3%
8%
Rye
1%
Wheat
37%
Corn silage
Corn grain
1%
4%
Barle y
2%
O at
1%
Rye
0%
Why the changes in crops grown
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Economics
Farm policies
Sensitivity of crops to extreme weather, resulting in disease and low yields of some crops.
High humidity conditions in the summers have caused an increase of fungal diseases. Barley acres have
decreased due to the outbreak of scab (Fusarium headblight). Sunflower and canola have increasing
problems with sclerotinia.
Not only is there an increase in diseases but weather conditions also have an effect on insects. For
instance, it was observed that soybean aphids over wintered in NW MN (winter of 2005-2006) and caused
an early outbreak of soybean aphids in the region in 2006.
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There are differences in crop tolerance to excess water. Soybeans have done well over the last few years,
even in early season excess moisture conditions.
Agronomists, bankers, and farm business management instructors, visited more than 30 farms for daylong evaluations. The majority of producers evaluated followed proper crop management practices;
however, yields varied greatly. All producers pointed to challenging water management issues on their
farm as the main cause for the yield variability. Global Positioning Systems have enabled producers to
use yield monitors on their combines and produce yield maps of fields. Yield maps have shown that there
is a correlation between excess moisture and low yields in the field.
Although the increase in laser technology has helped producers to improve field drainage, excess water is
still a major problem. Many soils in Minnesota and Canada have poor natural internal drainage and will
remain waterlogged for several days after excess rain without artificial drainage. This prolonged wetness
prevents timely fieldwork and causes stress to growing crops because saturated soils do not provide
sufficient aeration for crop root development. The roots of most crops grown in Minnesota cannot tolerate
excessively wet conditions for more than a few days.
Over the last decade producers have started to tile drain some of their most problematic fields. The results
have been promising.
Potential Benefits of tile drainage are:
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Increased crop yields are experienced with improved soil conditions.
Soil erosion will be substantially decreased because water will filter into the tile lines, instead of
running over farmland to waterways.
Less runoff of nutrients like phosphorous.
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Roots grow deeper into the ground and develop a more vigorous root system so crops are better
equipped to withstand drought conditions.
Soil damage will be reduced from compaction (caused by working wet soils with heavy
equipment).
Extended growing and harvesting seasons since producers will be able to begin planting and
harvesting sooner.
No more waiting for an entire field to be free of wet spots before working the field.
Better soil health as bacteria need oxygen.
Wider selection of crops and varieties due to less crop limitations.
Uniform yields on the whole field.
Saves wear and tear on equipment.
Not as many breakdowns. Save on parts and labor.
Lower fuel costs, easier to work fields when soil is friable.
Tiling is very important where organic systems are used.
Well drained farmland fetches a premium price when sold.
Rental rates for tile drained land are higher than non-tiled land.
Potential sub-surface drainage concerns
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Expensive
Potential increase of nitrates in drain water
Important to have the right design
Graph: Average Wheat, Soybean, and Sugar Yield In % of non-tiled 2001-04
Wheat (7)
Soybean (6)
Sugar (2)
115
Yield
Percent
110
105
100
95
90
0
0.25
Drainage Coefficient (inch water removal per 24 hours)
Source: Field research by Drs Gary Sands, Jochum Wiersma, Hans Kandel. Data for wheat, soybean and
sugar is from 7, 6, and 2 year/environments respectively.
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Research in Crookston and Brooks (both in NW Minnesota) confirmed that sub-surface drainage
increased the yield (around 10%), stabilize yield fluctuations over time, and made field operations easier.
Summary:
A) Producers are growing crops that are more adapted to the environment.
B) Producers have increased their water management in production fields.
C) Producers have increased attention to detail in the production systems; variety selection, fertilizer
management, fungicide application, automation, GPS, and yield mapping.
Resources:
The Drainage Outlet (D-Outlet) is the place where you can gain access to the world's online drainage
resources to discover and discuss current drainage issues, priorities, and activities. http://doutlet.coafes.umn.edu
Tile Drainage for Profitable Crop Production http://www.smallgrains.org/drainage/home.html
Sources:
Climate changes: Dr. Mark Seeley University of Minnesota Extension Climatologist.
Crop data http://www.nass.usda.gov/QuickStats/Create_County_Indv.jsp
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