How well am I doing?
Ways to reduce soil loss from your farm
Reduce the potential for water to cause erosion by:
• stoppingexternalwaterflowingontoandthroughyourpaddocks
• removingwatersafelyfrompaddocks
• reducingthespeedofwaterflowingacrosstheland
• creatingstableseedbedsthatresisterosion
• maintainingaprotectivegroundcover.
How well do you keep soil on your farm?
Havealookatthelistofactivitiesbelowandseehowmanyyouhaveinplace.Notallofthe
practiceswillberelevantorappropriatetoyourfarm,butasaruleofthumbyoushouldhaveat
leasthalfoftheminplacetoeffectivelyavoiderosionduringheavyrainfall.
Fact sheet
2
Managing soil erosion
in vegetables
Onlytickoffanactivityifyoucananswer‘yes’foralltherelevantareasofyourfarm.Forexample,
ifonlyhalfyourcultivatedpaddocksonslopinggroundhavegrasseddiversionbanksabovethem,
youwouldmarkit‘x’(notinplace).
Activity
Comments
Site selection
Iavoidgrowingvegetables
onslopesgreaterthan20%
Steepslopesobviouslycauserapiderosivewatermovement.The
preferredsloperangeforgrowingvegetablesis0%to10%.Slopes
above5%requiresoilconservationpractices.Slopesabove10%need
extensiveerosioncontrols.Thesesteeperslopesalsoposeother
problems,suchasunsafemachineryoperationsandinconsistent
irrigation.
Field layout and planning
Iusegrasseddiversion
banksabovemysloping
vegetableproductionareas
todivertexternalrunoff
Diversionbankswillpreventrunofffromhigherareasflowingontoand
throughcultivatedland,takingsoilwithit.Watershouldbediverted
tostablegrasseddrainageareasoutsidecultivatedpaddocks.
Ikeeprowlengthsshortby
insertingvegetatedcrossdrains(orheadlands)and
directingwaterfromthese
intoagrasseddrain
Shorterrowswillpreventwaterbuildingupandreducethespeedof
theflowdowntheinter-rows.Grassedcrossdrainsand/ormounds
slowwaterdownoverthesusceptibleinter-rowsoilanddirectitinto
grasseddrainageareasorstablewatercourseswheresoilcannotbe
eroded.
Queensland the Smart State
Yes (✓)
No (x)
or N/A
Activity
Comments
Iplanandpreparegrassed
drainageareasand
headlandsanddirectrunoff
water into these areas
Agoodcoverofgrassondrainageareas,headlandsandnonproductionareasprotectsthesoilfromwaterandwinderosion.
Iallowavegetated
bufferspaceofatleast
threemetresbetween
myvegetablecropsand
waterways
Athree-metregrassedbufferareathatfollowsthecontourwillfilter
sedimentandnutrientsfromwaterbeforeitentersthewaterway.
Thebufferareaneedstofollowthecontoursowaterwillmoveevenly
throughit.
Cultivation
Iavoidcultivatingthrough
drainageareas,natural
watercourses and low
pointsinapaddock
Ikeepthenumberof
cultivationsforseedbed
preparationtoaminimum
Runoffwaterwillflowfastandinlargequantitiesthroughtheseareas
duringstorms.Grassstabilisestheseareasandpreventserosion.The
vegetationmayneedregularslashingtoassistrapidremovalofwater
fromthepaddock.
Cultivationsresultinsoftanduncoveredsoil,whichisidealfor
erosion.Morecultivationskeepthesoilatriskoferosionforalonger
time,andeachcultivationcontributestostructurebreakdown,
compactionandreducedorganicmatter.Organicmatterimprovessoil
structure,whichwillmakethesoillesslikelytoerode.
Sprayingoutfallowcovercropsorvolunteergrowthwithherbicide
ratherthancultivatingtostartseedbedpreparationisonewayto
reducethenumberofcultivationsandthetimesoilwillbeuncovered
duringseedbedpreparation.
Iminimisetheuseof
cultivationequipmentthat
is hard on soil structure
Rotaryhoesanddisccultivatorsusuallycausemoresoildamagethan
tynedandnon-invertingimplements.
Iavoidcultivatingduring
timesoftheyearwhen
heavyrainfallislikely
Heavyrainfallcanhappenatanytimeofyear,butismorelikelyin
springandsummerinQueensland.Itwon’talwaysbepossibleto
avoidstormsonfreshlycultivatedsoil,soothererosioncontrol
practicesneedtobeinplacetoreduceproblems.
In-field practices
Iallowvolunteerplantsto
growwhenthevegetable
cropisfinishedtohave
soilcoverduringthefallow
period
Somecoverisbetterthannocover,andnaturalgrassesandother
volunteergrowth(weeds)canprovidethis.Ifusingthisoption,you
mustspot-controlinvasive(noxious)weedsandpreferablyslashor
killthevolunteergrowthbeforeweedseedsareformed.Growing
bulkycovercropsisabetteroptionbecausetheyaddmoreorganic
mattertothesoilandtheweedseedproblemisavoided,butthiscan
belimitedbytheamountofwateravailabletogrowthecrop.
Igrowbulkycovercrops
orcommercialcropsin
rotationwithvegetables
Bulkycovercropsmaintainbettersoilcoverthanvolunteergrowth
outsidevegetableproductionperiods,andaddmoreorganicmatter
tothesoilwhenincorporated.Thecovercropmaybeapastureor
cerealspeciesthatisnotharvestedforprofit,orabulkycommercial
cropsuchassorghum,sweetcornorsugarcane.Mostgrowerswould
notcontemplateirrigatinganon-commercialcovercrop,soitwill
dependonrainfallduringthefallowperiod.Commercialcropsbeing
rotatedwithvegetableswouldneedtobeirrigated.
Iaddlotsoforganicmatter
tomysoil
Organicmatterbenefitsthesoilinmanyways,includinghelpingto
bindsoilparticlestogether,makingthesoilmoreresistanttoerosion,
particularlysandsandsandyloams.Theorganicmattercanbeadded
asasoiladditive,suchassugarcanetrash,millmud,hayorcompost.
Acheaperalternativeistogrowbulkymulchcropsandcultivatethem
intothesoilorspraythemoff.Thisformsasurfacemulchthatthen
breaksdownintothesoil.Organicmattermustbelargelybroken
downbeforevegetablecropsareplantedotherwisedamping-offcan
causeplantlosseswithsomecrops.
Yes (✓)
No (x)
or N/A
Activity
Imaintainapermanentsoil
covermulchbygrowing
abulkyfallowcropand
slashingorsprayingit
outbeforeplanting,then
annuallyplantingfallow
andvegetablecropsinto
themulch
I control weeds in the
cropbymeansotherthan
soilcultivation(suchas
mulching,herbicides,
flame)
Comments
Inthisexperimentalsystem,calledareducedtillagesystem,
machinerythatcansoworplantintothemulchlayerisneeded.The
soilisnotcultivatedforseed-bedpreparation.Themulchprovides
permanentsoilcoverandimprovessoilhealth.
Thissystemappearstobeeasiertomanageintemperateclimates,
butisbeingtrialledintropicalandsubtropicalareas.
Cultivationresultsinbaresoiland,overtime,poorsoilstructure,
reducingthesoil’sabilitytoresisterosion.
Covercrops,suchasoatsormillet(inautumn/winter)orsorghum(in
spring/summer),willreducesoilerosionfromwaterrunningdownthe
inter-rows.Inter-rowwatervolumesaregreaterwhereplasticmulchis
used.
Iplantinter-rowmulch
crops once crop beds are
formed
The‘livingmulch’canbeslashedorsprayedwithherbicide(ora
combinationofthese)beforeitseeds.Thelivingcropbindsthesoil
andslowswaterflow.Thedeadinter-rowcropwillformamulchcover
alongtheinter-rowandcontinuetoprotectthesoil.
Themulchcropcouldbegrown,sprayedoutandflattenedbefore
vegetableplantingtoavoiddiseaseriskorstandingmulchinterfering
withothercropmanagementactivities.
Streams, major drains and buffer areas
Ikeepbufferanddrainage
areas outside the crop
coveredwithgrassorother
vegetation(notnoxious
weeds)
Couchorcarpetgrassaresuitablefordrainageareas.Deepdrainsor
steepbaredrainsectionswouldbenefitfromatoughdeep-rooted
species,suchasvetivergrass,tostabilisethesite.
Imaintainnative
vegetation,orhave
replantednativevegetation,
onandnearthebanksof
waterwaysrunningthrough
oralongsidemyproperty
Vegetationactstostripsilt(andtosomeextentnutrients)fromrunoff
waterenteringcreeksandstreams.Nativetreesandshrubswillalso
stabilisethestreambanks.
Imaintainsilttrapsordams
instrategicdrainageareas
onmyproperty
Silttrapsordamsslowrunoffwatersothatsiltisdepositedinthe
trapordam.Ifthetrapsoverflow,onlytheheavierfractionofthesoil
iscaught,andthemorefertilefineclayparticles,alongwithorganic
matterandnutrients,arelost.Silttrapsmustbelargeenoughto
handlethevolumeofrunoff,andbeabletoholdwaterlongenough
forsilttodropout.Thebeststrategyistopreventsoillossfrom
paddocksinthefirstplace.Silttrapsarereallyabackupandaremost
usefulincombinationwithothererosion-preventingstrategies.
Farm roads and tracks
Idesignandsitefarmroads
andtrackssotheyhave
lessthan10%grade,have
aslightcrownorcross
slopeand(wherepossible)
aresitedonridgelinesor
embankments
Iusediversionbanksto
preventrunofffromupthe
slopeflowingontoroads
andtracks
Thisreducesthelikelihoodofalotofwaterpoolingandflowingdown
roadsandtracks.Onceatrackbecomesadrain,itwillquicklyscour.
Erodedroadsandtracksnotonlycontributesoiltowaterways,but
affectaccessandproductqualityfromfieldtopackhouse.
Thisappliestoroadsandtracksrunningacrossslopes.Diversion
banksonthetopsideofthetrafficwaycanredirectwatertograssed
drainsorunder-trackculverts.
Yes (✓)
No (x)
or N/A
Activity
Comments
Imaintainearthbanks
ondirtroadsandtracks
runningdownhill.
Earthbanks,or‘whoa-boys’,constructedatregularintervalsata
slightangleacrossroadsandtrackshelppreventwashouts.Ensure
thewaterisredirectedintoastabledrainalongsidetheroadortrack.
Iuseculvertsorpipes,
orbuildbridgestolift
trafficwaysoverdrainsand
streams.Alternatively,I
stabiliseroadsandtracks
crossingthroughmajor
drainsandstreams
Trafficthroughwetandmuddydrainageareasandcreeksstirsup
thesoil.Thissoilistheneasilymovedintowaterwaysandother
environmentallysensitiveareasfurtherdownstreamwhenthedrains
andcreeksflow.Culverts,pipesandbridgescarrytrafficoverthe
drainsandcreeks.Stabilisedcrossings(orfords)throughdrainsand
creeksareanotheroption.Crossingscanbestabilisedusingmaterials
suchasconcrete,stonesorbluemetalwithadiameterofatleast
50mm.Alloptionswillneedregularmaintenance.
Yes (✓)
No (x)
or N/A
How did you score?
Ifyoutickedfewerthan12activities(meaningyouhavefewerthan12oftheseactivitiesinplaceonyour
farm),thenyouneedtodomoretocontrolerosion.Don’tbecomecomplacentbecauseofthedrought.
Onebigstormandyoucouldlosealotofyoursoil.
Ifyoutickedmorethan12activities,thenyouaredoingOK.Youonlyneedtoconcentrateonthegaps
identifiedfromcompletingthischecklist.Whatelsecouldyoudotoreduceerosion?Marktheideasyou
canuseandputthemonyourlistofthingstodo.
More information
• ‘Managingsoilerosioninvegetables:seewhat’sworkingforSouthEastQueenslandgrowers’is
availablefromtheDepartmentofPrimaryIndustriesandFisheries(DPI&F).
• Healthysoilsforsustainablevegetablefarms–UteGuide(AUSVEGLtd2007)ContactAUSVEG:
Tel: (03)95448098
Fax: (03)95586199
Email: [email protected]
• SoilerosionfactsheetsfromNSWDepartmentofPrimaryIndustriesareavailableat
www.agric.nsw.gov.au(goto‘Naturalresources,environmentandclimate’,then‘Soilhealthand
fertility’,then‘Soilerosion’).
Acknowledgements
ThisfactsheetwasproducedaspartoftheSustainableAgricultureState-levelInvestmentProgram
(AgSIP)project‘Horticultureindustrycapacitybuildingandscopingofnaturalresourcemanagement
issuesinthedrytropics’.ThankyoutoBundabergFruitandVegetableGrowers,Burnett-MaryRegional
GroupforNaturalResourceManagementInc.andGrowcomfortheirsupportofthisproject.The
AgSIPProgramwasfundedbytheNationalActionPlanforSalinityandWaterQuality(Australianand
Queenslandgovernments)andledbytheDepartmentofPrimaryIndustriesandFisheries.
For more information, contact:
JohnBagshaw
SeniorExtensionHorticulturist
DepartmentofPrimaryIndustriesandFisheries
[email protected]
or
DepartmentofPrimaryIndustriesandFisheries
BusinessInformationCentre
Tel:132523(costofalocalcallwithinQueensland)
Interstate callers:(07)34046999
Email:[email protected]
Web: www.dpi.qld.gov.au
Fax: (07)34046900