Soil health and howSoilhealthandhowto measure ittomeasureit

LoriHoagland

AssistantProfessor

DepartmentofHorticulture&L d A hiLandscapeArchitecture

PurdueUniversity

Outline

Wh t i il h lth d h h ldWhatissoilhealthandwhyshouldwecareaboutit?

Whatconstituteshealthysoil?

Howcanyoubuildsoilhealth?

H il h lth?Howcanyoumeasuresoilhealth?

Whyshouldyoucarey yaboutsoilhealth?

Analogy

Youregoingonatrip whichtiresdoyouwant?

Leakytires FullyinflatedtiresOR

EricBrennan USDAARS

Analogy

P il= PoorsoilqualityqualityLeakytiresy

Whatissoilhealth?

Definition: The capacity of a living soil to:Definition:Thecapacityofalivingsoilto: functionwithinnaturalormanaged

b d iecosystemboundaries sustainplantandanimalproductivityp p ymaintainorenhancewaterandair

litquality promoteplantandanimalhealthp p

(Doranetal.,1996,1998)

Whycareaboutsoilhealth?

Alleviate soil compactionAlleviatesoilcompaction

Increasewaterinfiltrationandwaterholdingcapacity

R d i i i d i hReduceirrigationcostsandimprovethepotentialforyoursoiltowithstanddrought

R d i d k il i lReduceerosionandkeepyoursoilinplace

Consequencesofpoorsoilhealth

A single inch ofAsingleinchoftopsoilcantake500

yearstoformnaturally

Erosion in the Palouse

SurfacerunofffromafarmfieldinIowaduringarainstorm

naturally

Columbia River Basin from space Fall 2009

g

Whycareaboutsoilhealth?

Reduce incidence of pest outbreaks andReduceincidenceofpestoutbreaksandlowerpesticidecosts

Increasenutrientholdingcapacityofthe

soil reduce nutrient loss and lowersoil,reducenutrientlossandlower

fertilizercosts

Improvecropproductivityandqualityofyour produceyourproduce

Whatconstituteshealthysoil?y

ComponentsofsoilhealthChemical wellunderstoodandapplied

Physical fairlywellunderstood but not

Biological theleastunderstood andunderstood,butnot

oftenappliedMoebius, 2004

understoodandapplied

Relevanceofchemicalsoilhealth

pH measureofacidityoralkalinityofthesoil

impacts:

nutrientavailabilityy

availabilityoftoxicmetals

activities of microorganisms activitiesofmicroorganisms

thatfacilitatenutrient

li d d dicyclingandreducedisease

risk

Relevanceofchemicalsoilhealth

Salinity saltcontentofthesoili i i i f ili d inirrigationwater,fertilizers,compostsandmanure

accumulationcandegradesoilstructureandrestrict

vegetablegrowth

Cation exchangecapacity quantityofcations inthesoil cation isapositivly chargedion(ie.Ca2+,Mg2+, NH4+,

Zn2+,Cu2+,Mn2+)

dependsonamountofclayandorganicmatterinthesoil

impactsthesoilsnutrientholdingcapacity

Relevanceofphysicalsoilhealth

Soiltexture proportionofsand,siltandclayparticles in the soilparticlesinthesoil

functionofsoilsparent

material

virtually unchangeablevirtuallyunchangeable

exceptthrougherosion

importantforsoiltest

interpretation

Relevanceofphysicalsoilhealth

Soilstructure(ortilth) arrangementofsoilparticlesinto aggregatesintoaggregates canchangerapidlyinresponsetomanagement

T th t t d t tTogethertextureandstructure

impact:W t d t i t h ldi itWaterandnutrientholdingcapacity

Waterinfiltration

Aeration Aeration

Seedgerminationandrootproliferation

Biologicalactivity

Moebius, 2004

g y

Erosionpotential

RelevanceofbiologicalsoilhealthItsAlive!Megafauna mice,ants,

earthworms spiders etcearthworms,spiders,etc.

initiateorganicmatter

decompositiondecomposition

aeratethesoil

f dMesafauna nematodes,

mites,springtails

regulatemicrobial

populations

Microfauna bacteria&fungi

Regulatenutrientcycling

Improveplanthealth

Rhizosphere zoneofgreatest

RootssupportmicrobesMicrobesaidplants

microbialactivityRhizobia

Releasesignals&

Fixnitrogen

Solubilizephosphorous

ppp

gnutrients

Enhancerootgrowth Provideprotection

Suppressplantpathogens

Morebenefitsofsoilbiologicalhealth

Buildsoilaggregates secretebiologicalglue

Filter and detoxify chemicalsFilteranddetoxifychemicals

Make that sweet smellMakethatsweetsmell Streptomyces&geosmin

Guides camels Guidescamels

Glomalin productionbymycorrhiza

Howcanyoubuildyhealthysoil?y

Addorganicmatter

Beneficialimpactsonsoilproperties:

Chemical higherCEC,pHbuffer,tiesupmetals,interactswithxenobiotics

Physical stabilizessoilstructure,improveswaterholdingcapacity,reducedcompaction,darkcolorhelpswarmsoilp y, p , p

Biological suppliesenergyandbodybuildingconstituentsf il i d i k f t i t ( ilforsoilorganisms,sourceandsinkfornutrients(soilfertilitybankaccount),ecosystemresilience

(H.Atthowe)

Applybiologicalamendments

Eric Zakarison demonstrates his solorpowered tractor

Plantcovercrops

Reducetillage

Notillvegetabletransplanter

http://www.separcd.org/notill_vegetables.htm

Restoringorganicmatter&soilhealth

(BradyandWeil,2002)

Restoringorganicmatter&soilhealth

S il h lth Silt l Silt L Cl L Cl L

ImpactoftillageonsoilphysicalhealthSoil health indicator

Silt loamPlow till

Silt LoamNo - till

Clay LoamPlow till

Clay LoamNo till

Bulk density Not Not 1.21 1.03y(g/cm3) significant significantPores > 30 microns (%)

13 17 12 16

Pores < 30 microns (%)

Not significant

Not significant

29 24

Available water 12 16 Not significant Not significantcapacity (%)

Water stable aggregates

20 41 30 68aggregates 0.25-0.2 mm (%)

(Idowu etal.,2006)

Restoringorganicmatterandsoilhealth

Impactoforchardfloormanagementonsoilhealth

compostapplicationcoupledwithhightillagedoesnot

positivelyimpactsoilhealthcharacteristics

covercropsresultindramaticimprovementinsoilphysical,

chemicalandbiologicalproperties

RestoringorganicmatterandsoilhealthRestoringorganicmatter&soilhealth

ImpactofwheatcultivationonFluorescentPseudomonans

oil

Managingsoilbornepathogensinapplewithwheatcultivation

60

80

100

eudo

mon

asg

1so

b

a

ab

a a

0

20

40

Control Pasteurized Wheatgrass Modern Wheat

Organic Wheat

Perennial Wheatof

Fluorescentps bc

c

Wheat Wheat Wheat

60

Impactofwheatcultivationonsoilbornepathogens

#o

sg

1 soil

a

2030405060

borne

patho

gens

bb

ccc

010

Control Pasteurized Wheatgrass Modern Wheat

Organic Wheat

Perennial Wheat

#ofsoil

(Hoaglandetal.,2010)

Canyouaddtoomuchorganicmatter?

Material C:NMicrobialTissues 612:1

InsomecasesyesSoilHumus 1012:1AnimalManure 1325:1LegumeResidues/GreenManures 1325:1Compost 25 30:1

Nutrientimmobilization

WatchthesaltCompost 2530:1CerealResidues/Straw 6080:1ForestRefuse 150500:1

Carefulwithnewly

incorporatedfreshp

residues

Requires careful 50006000

il

Tukey

PAR

ImpactofBrassicaseedmeal incorporationonPythium

Requirescareful

management1000

2000

3000

4000

cfu

pyth

/ g s

oi IRRECHULTHETATT

0Cnt Past. Bj Sa Bn Gm

ATT

Control Pasteurized

(Hoaglandetal.,2008)

Howcanyoumeasureysoilhealth?

Standardfertilitytestatacommerciallab

Recommended every 35 yearsRecommendedevery3 5years

Generallycost$1020

Typicallyincludes:pH,availablephosphorous,nitrogen,potassium,calcium,magnesiumandorganicmatter

Collectingthesoilsample

Sampleatthesametimeeachyeartoachievemoreaccurate trendsaccuratetrends

Tools:samplingtubeorspade,buckets,plasticbags

Collectrepresentativesample

Soiltype,managementpractices,crop

growth&yield

Avoidirregularareas

2030coresper1020acrefield

Collectsamplestoadepthof approximately8

Mixandairdry

CornellSoilHealthLab

Basictest($40) Comprehensive($65) Standardsoilfertilitytest(pH,OM,P,K,Ca,Mg,Al,Fe,Zn,Mn)

P ti l i di t ib ti

Basictest

Potentiallymineralizable

i ( ) Particlesizedistribution

Wetaggregatestability

Available water capacity

nitrogen(PMN)

RoothealthbioassayAvailablewatercapacity

Surfacehardness

Activecarbon

*Samplesshouldbetakeninthespringpriortotillage

http://soilhealth.cals.cornell.edu/extension/test.htm

SoilFoodWeb

Soilfoodweb

http://oregonfoodweb.com/

Measuringsoilhealthonthefarm

NRCSSoilQualityTestKit Electricalconductivity&pH

Soilnitrate

W t i filt ti & t litWaterinfiltration&waterquality

Bulkdensity

Aggregate stabilityAggregatestability

Slaketest

Soilrespirationp

Earthworms

Measuringsoilhealthonthefarm

Soilqualityscorecards subjectivetestsbasedonfeel,siteandsmell

Mayincludecharacteristicssuchas: Earthworms

Organicmattercolor

Waterholdingcapacity

Drainage/infiltration

Organicmatterroots/residues

Subsurfacecompaction

S il il h/f i bili / ll

Cropcondition

pH

N t i t h ldi it Soiltilth/friability/mellowness

Erosion

Nutrientholdingcapacity

TalktolocalNRCSoffice

Interpretingresults

Dependson:p

soiltype

crops grown cropsgrown

farmsizeandmanagement

Usetoevaluatechangesinpracticesovertimep

Practiceonfarmexperimentation

ResourcesBuildingSoilsforBetterCrops Fred Magdoff and Harold van EsFredMagdoff andHaroldvanEs

SustainableAgricultureNetwork

http://www.sare.org/publications/soils.htm

SustainableSoilManagement SoilSystemGuide ATTRAATTRA

http://attra.ncat.org

Natural Resource Conservation ServiceNaturalResourceConservationService

PurdueExtensionEducators

LoriHoaglandlhoaglan@purdue.edu