PowerPoint Presentation

Was Dr. Albrecht Correct? Great Plains Growers Conference

Tim ReinbottUniversity of MissouriColumbia MO 65201

University of Missouri Bradford Research Center:

In MO and Other States The Standard Soil Test Based Upon Sufficiency

Basic Soil Test Results

For Gardens MU Has A Recommendations Guide

pH Recommendations And How To Fix

Nutrient Recommendations

What Are The Basics of the Albrecht System?Ca:Mg Ratio-68:12

What Does Too Much Mg Do?

K-Balance: 2-5%

P-Adequate Amounts

Sulfur-Is it important?

Micros-Cu, B, Zn

Is Dr. Albrecht Correct?Does The Ca:Mg Ratio Really Make A Difference?

Are Micros Really That Important

Sulfur?

OriginalSoil Analysis

-Very Balanced-Required N,P, K, S-Micros-Zn, Cu, B-Pell Lime

Our Soil-Alfisol, Thin Loess Cap, Claypan

Soil Nutrient Content at Various Depths-A lot of Ca, Mg, P, and K in the Subsoil

From MU Bradford-2012

Setup TreatmentsNo P, K, S, Micros or anything else except NKinsey RecommendationsNPKS only not microsKinsey Recommendations except KMg usedKinsey Recommendations except KMg and no Pell limeN plus micros only

Research Plot Planting

Corn Plots at Harvest

2013 Corn Yield

2014 Same Treatments As 2013 Even Though The Soil Tests Had ChangesNo Pell Lime Recommendations

2014 Corn YieldUtilizing 2013 Recommendations

Changes In Soil Test-Initial (left) Recommendations plus Mg (right)

Mg Level has goneup.Much more Ca is Needed to keep balance

Changes In Soil Test 2015:Initial (right) and P and K only (left)

Ca:Mg is now 57:14Requires Lime andMg

2015 Based Treatments on Soil Test

Soybean Yield 2015TreatmentYieldControl42Recommendations45PKS only43Recom.+Mg41Recom. No lime +Mg39Micros only40P and K only35

ConclusionsFollowing the Kinsey/Albrecht Recommendations increased corn and Soybean yieldAdditional Mg did not reduce corn in Year 1 and 2 but did reduce soybean yield in Year 3

Additive effects of PKS and Micronutrients

Importance of following soil test recommendations each year

What Is Going On?

Dr. Albrecht Was a Soil Microbiologist

The soil microbes in the plow layer has the mass equivalent of two cows (2400 lbs) per acre that need to be fed Soil organisms are much like cows, they need inputs of plant residues for food and energy

Specifically, they need the carbon that is contained in plant residue and soil organic matter

Plant Residue Feeds The Bacteria, Fungi, and other Life

SOM & RootsSOM is NOT just from crop residues but also from the Root Exudates!28

SOM is NOT just from crop residues! Plant roots are very important to SOM production. Living plants (i.e, cover crops) help retain and PRODUCE SOM.28

The Decay Zone: Top 0-6 inches in the Soil

Our Goal Is To Have Something Living on the Soil Year Around and For There To Be Diversity

With grain production that means cover crops

But What Have We Done To Our Soil?

100+ Years of Tillage Has Severely Reduced Soil Organic Matter and Soil Micro Organisms

Small changes in SOC resulting from changes in management practices can have large effects on soil behavior and microbial processes.

Tilled vs No-Till-We Have Destroyed Much of Our Soil StructureLong Term PastureTilled in a Corn/Soybean/Wheat Rotation

What Does Organic Matter Do?Nutrient CyclingNutrient Holding CapacityPool of NutrientsFood for soil organismsWater DynamicsImproves water infiltrationImproves water holding capacityStructureReduces crusting, compaction, erosionEncourages root development

What Did My Garden Look Like After A 2 inch Rain?

Cover Crops in 2014-Oats and Legumes

All organic matter in soil is not equalScientists describe 3 pools of soil organic matter **really is a continuum of decomposition38Passive SOM500 5000 yrsC/N ratio 7 10

Active SOM1 2 yrsC/N ratio 15 30

Slow SOM15 100 yrsC/N ratio 10 25

Recently deposited organic materialRapid decomposition10 20% of SOMIntermediate age organic materialSlow decomposition10 20% of SOMVery stable organic materialExtremely slow decomposition60 80% of SOM

CO2Organic Material

38Soil organic matter (SOM) is composed of the living (microorganisms) not considered part of SOM by most scientists, though, the dead (fresh residues, active C), the really dead intermediate fraction = slow fraction, and the really, really dead (humus) fraction = passive.

Results are read in a spectrometer in lab or field or from a color card

Potassium Permanganate Test

KMnO4 oxidizes active carbon. The purple color of the chemical changes to pink the more active carbon there is in a soil sample.

Active Carbon in Soil Organic Matter-The Lighter the Color the MORE Active Carbon

Active Carbon-More In Permanent Polycultures-Cover Crops More Than No-Till

How Did Our Treatments Affect Active C?

How Did Our Treatments Affect Soil C and Soil N?

Mother in Law-Her First Garden Was Her Best Garden

What Was Her Garden Before It Was A Garden?

What Has Most Abundant and Diverse Soil Microbes?

No-Till With Cover CropsNo-Till In A Corn/Soybean Rotation

Tilled Each Year in a Corn/Soybean Rotation

What Has Most Abundant and Diverse Soil Microbes?

FencerowNative Warm Season Grass

Cool Season Grass Mix

Restored Native Prairie

Is There A Difference in Soil Microbes With Vegetables Under Plastic or Straw?

Cover Crop Under Plastic Did Not Decompose-Less Microbial Life?

How Do Soil Microbes, Soil Carbon, and Nutrient Balance Interact?

Soil Structure arrangement of soil solids and voidsinfluences water infiltration and retention, erosion, crusting, nutrient recycling, root infiltration and crop yieldexpressed as degree of aggregate stabilityaggregation is controlled by SOC, microorganisms, ionic bridging, clay

http://vro.dpi.vic.gov.au/dpi/vro/vrosite.nsf/pages/soilhealth_soil_structure

http://ecomerge.blogspot.com/2010/05/what-soil-aggregates-are-and-how-its.html

Calcium Influence on Soil StructureSoil StructureThe grouping or arrangementof individual soil properties into a larger grouping.(Also called aggregate, ped)

Formation of Soil StructureFlocculation: Bringing the particles close together, enhanced by polyvalent cations (Al+++, Ca++, etc.). Mg is not as good as Ca in flocculation.

Stabilization: Providing durability to maintain the arrangement. Some clay; organic matter; oxides of Fe and Al.

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Aggregate Stability: Interaction of Soil Microbes, Clay, Ca, and Humus

From Muneer and Oades, 1989

Aggregate Stability:Interaction with Ca, Humus, Clay

From Muneer and Oades, 1989

Aggregate Stability-How Quick Can it Change?

Influence of Structure on Water Movement

Granular Prismatic Blocky PlateyFlocculated by Ca Restricted Enhanced by OM Movement

Aggregate StabilityFungal-produced glomalin helps bind aggregates

Measured with wet sieving

http://ed.fnal.gov/trc_new/pandp/soil_research/soil_aggregates.html

Wright, et al., 1999

Tillage Destroys Aggregate Stability

My son doing his favorite thingAfter a two inch rain

Water Infiltration

Good infiltration allows for less runoff and erosion

Soils with poor aggregate stability will crust, damaging emerging seedlings and increasing runoff

Aggregate Stability-Better Water InfiltrationFungal-produced glomalin helps bind aggregates

http://ed.fnal.gov/trc_new/pandp/soil_research/soil_aggregates.htmlWright, et al., 1999

Tillage reduces aggregate stability and sizesChen et al., 2000

The Slake Test Video

ConclusionsSoil Microbial biomass is important

Interaction of soil microbe excretions and Ca on soil aggregate stability

Balanced soils produce more biomass; above and below ground and in return feed microbial system

Questions?Tim ReinbottUniversity of MOReinbottT@missouri.edu