1 / 28

Ag Expo 2004

Soil Management for Higher Yields. Ag Expo 2004. Greg Schwab and Lloyd Murdock Extension Soil Specialists UK Department of Agronomy. Nitrogen Deficiency. Low Soil pH. Idealized Kentucky Soil . Air 25%. Soil Minerals (Silt loam) 47%. Water 25%. Organic Matter 3%. Air 5%.

Ava
Download Presentation

Ag Expo 2004

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Soil Management for Higher Yields Ag Expo 2004 Greg Schwab and Lloyd Murdock Extension Soil Specialists UK Department of Agronomy

  2. Nitrogen Deficiency

  3. Low Soil pH

  4. Idealized Kentucky Soil Air 25% Soil Minerals (Silt loam) 47% Water 25% Organic Matter 3%

  5. Air 5% Water 20% Soil Minerals (Silt loam) 72% Compacted KY Soil Organic Matter 3% Macropores are compressed soil oxygen decreased dramatically Effects Poor Drainage Slow Root Growth

  6. Depth of compaction as (6) axle load and (7) soil moisture increases (Tire pressure remained at 12 psi for all tire sizes) (Tire size 11 x 28, load 1,650 lbs, pressure 12 psi)

  7. Proctor Compaction Curve Optimum M.C.=14.3% for a silt loam Potential Compaction 8 10 12 14 16 18 20 22 Soil Moisture Content (%)

  8. BUT allows operations in wetter conditions and compacts a greater soil volume. More tires will spread weight …

  9. There really are days we shouldn’t be in the field ! (Even if equipment lets you) Sometimes we need to admit …

  10. Compaction SurveyMurdock and County Agents1992-1993 • Categories • Little or None – Less than 30% of penetrometer readings in field were 300 psi or greater • Slight – 30 to 50% of the penetrometer readings were 300 psi or greater • Moderate – 50-75% of the penetrometer readings were 300 psi or greater • Severe – 75 to 100% of the penetrometer readings were 300 or higher

  11. Stunting, uneven stands are often the first symptoms

  12. Compaction SurveyMurdock and County Agents1992-1993 • Results • Little or None – 46% • Slight – 18% • Moderate – 18% • Severe – 18% • By Drainage Class • 77% of poorly drained fields had moderate to severe compaction • 20 % of well drained fields had moderate to severe compaction 169 Fields

  13. Compaction SurveyMurdock and County Agents1992-1993

  14. Higher Yield Potential?

  15. Effects of Compaction on Crop Yield • Corn and Tobacco • Extreme 30-50% Yield Reduction • Severe 10-20% Yield Reduction • Moderate 5-10% Yield Reduction • Soybean and Wheat • Extreme 15-25% Yield Reduction • Severe 5-10% Yield Reduction • Moderate <5% Reduction

  16. Soil Compaction Questions • How much will it decrease yields? • Will deep tillage restore all of yield potential? • How long will compaction last? • Are penetrometers a good measure?

  17. Soil Compaction Effects on Corn and Soybeans Lloyd Murdock and John James, Princeton, KY Methods • Zanesville silt loam • Tilled and no-tilled areas • Treatments • Compacted • Compacted & Subsoiled • Uncompacted • Multiple passes of 10 ton equipment • 12 inches in depth • Tilled 6 in. each year

  18. Effect of Soil Compaction on Corn and Soybean Yields With and Without Compaction and Subsoiling *Treatment subsoiled only in fall of 1999

  19. Effect of Soil Compaction on Corn and Soybean Yields With and Without Compaction and Subsoiling *Treatment subsoiled only in fall of 1999

  20. Effect of Soil Compaction on Corn and Soybean Yields With and Without Compaction and Subsoiling *Treatment subsoiled only in fall of 1999

  21. Results • Tilled compacted yields were 75% of check and improved to almost 90%. • No-tilled compacted yields were 2% of check and improved to 90% rapidly • Recovery beyond 90% will probably be very slow • Rapid no-till recovery is probably due to high rate of biological activity

  22. Soil Compaction?

  23. QUANTIFYING COMPACTION • Crop and Soil Symptoms • Penetration Resistance • Moisture Dependent • No Absolute Value • Note Depth and Relative Force • Compare Good and Bad Areas • Bulk Density • Mass per Volume • Calculate Porosity • Texture Dependent

  24. Percent Readings Treatment No-Till Tilled 1997 100 94 1998 100 94 1999 88 94 2000 75 100 2001 88 100 2002 88 100 Effect of Time on the Percentage of Soil Penetrometer Readings Over 300 psi in Compacted Tilled and No-Tilled Treatments.

  25. COMPACTION AFFECTSNUTRIENT UPTAKE Potassium Affected Most • Compaction Reduces Porosity • Lowers Soil Oxygen • O2 Needed for Root Respiration and Active Uptake

  26. Organic Matter and Soil Compaction

  27. Conclusion DETERMINE THE NEED FOR SUBSOILING • Evaluate Depth and Severity of Compaction • Check with Penetrometer, Probe, Shovel • Dig Plants to Examine Roots • Leave Untreated Strips for Comparison

More Related