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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lity,

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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

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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