Download - Cover crop benefits on claypan Soils
COVER CROP BENEFITS ON CLAYPAN SOILS
Newell KitchenUSDA-ARS Cropping Systems and Water Quality Research UnitColumbia, MO
Translating Missouri USDA-ARS Research and Technology into Practice A training session provided by USDA-ARS-CSWQRU, 10-11 October
2012, Columbia, MO
Why do we do cover crops?
We Need Cover!Cover:
blanket, canopy, cloak, hood, layer, shield, overlay, veil,cap
Poorly-Drained Upland Soils are not Exempt
Lost topsoil from erosionLost organic matterLost soil structureLower fertility
What essential is “cover” when you’ve lost 60-90% of the function of that original soil?
How have we incorporated cover crops on the Precision Agriculture System (PAS)?
2005 , 2007, 2009 Wheat Cover
2006, 2011 Cereal Rye
2007 Sudex (following wheat)
2008 Rye Grass
2009-2012 Grass/Legume/Brassica Mix
What benefits do we see with cover crops?
Mulch tillage, Corn-soybean rotation (MTCS)
No-till, Corn-soybean-wheat rotation (NTCSW cover)
Quickly shows reduced erosion
Improved Water Quality
What are the hidden below ground impacts of cover crops?
CRP (cool)
CRP (warm)
hay (cool & warm)
Improved Water Infiltration
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Footslope Backslope Summit
Landscape
Agg
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te s
tabi
lity,
%
Min. Till CS (1)No Till CS (2)ICM No Till CSW (5)CRP (6)
Improved Soil Aggregate Stability
Avg. N O 3-N (kg ha -1 90cm -1) C over: 16.7 N o-C over: 118.8
0 20 40 60NO 3-N (kg ha -1)
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Pro
file
Dep
th (c
m)
Recovered Nitrogen after Drought
Changes in other Soil Quality Indicators
Property and units 2003 2007 pH 6.18 6.34 P, mg/kg 7.6 15.1 K, mg/kg 60.9 133.6 SOC, g/kg 11.5 12.4 POM-C, g/kg 1.49 2.51 MnOxC, g/kg 0.344 0.342 Total N, g/kg 1.07 1.18 POM-N, g/kg 0.117 0.166
Highlighted items are significantly different between samplings
Typical Positive Impacts from Cover Crops on Soil Physical Properties
• Increased soil organic matter• Enhanced infiltration• Enhanced aeration• Improved soil structure/aggregation• Decreased soil strength• Preventive of soil compaction• Reduced evaporation potential