DEEPRIPPINGTOENHANCE PRODUCTION
Deep ripping has been shown to provide significant yield benefits on sandy soils acrossmultiplelocationsthroughtheMallee region.
Withmanyfarmersnowadoptingthispractice, therearenowimportantquestionsaroundhow ripping can be implemented to achieve the greatestbenefitinthemostcost-effectiveway.
MalleeSustainableFarmingwithfundingfromthe SouthAustralianGrainIndustryTrust(SAGIT) hastackledthisissuethroughtheproject“Deep RippingtoEnhanceProductiononMalleeSandy Soils".
Thisdocumentsummarisesthekeyfindingsfrom thisprojecttoprovideguidancetoMalleefarmers lookingtomaximisebenefitsfromdeepripping operations.
Soilloosening
Theresearchlookedatthesoillooseningabilityof deeprippingtynesworkinginMalleesandysoils atdepthsof400millimetresand600millimetres.
Following the ripping operation, soil pits were excavated,anddigitalimagingusedtoquantify thecross-sectionalareaoftheloosenedprofile. Atthe400mmdepth,eachtynelooseneda cross sectional area of 026 m2 and this increasedto044m2whentherippingdepthwas 600mm.
Theadditionofwingstothedeeprippingtyne improvedsoilloosening Awingwasfittedjust aboveandjustbehindthemaintipofthetyneto continuethesoilliftthatstartsatthetipofthe foot and to increase the width of loosening (Figure1).
Theadditionofthewingincreasedloosenedarea by49%to53%whentheoperatingdepthwas 400mmand600mm,respectively(Figure2). Atdeeperworkingdepths,theadditionofthe wingimprovedrippingefficiencywithsoil looseningincreasesof~50%,whiletheadditional draughtforceincreasedbyonly24%(Figure3).
Figure1.Astraightlegrippertyne(left)andfittedwith wings(right)
Figure2.Crosssectionofloosenedsoilareafortynes workingat400mmand600mmdepth,withand withoutwings
Figure3.Draughtforcerequirementsforastraightshank rippingtynewithandwithoutwingsrippingtoadepthof400 or600mm
Page1
StrategiestomaximisethebenefitsfromdeeprippingsandysoilsintheMallee
Cropresponsetosoilloosening
Theextentofsoillooseninghasadirect influenceonthecropresponsetodeepripping.
AtWoodleighintheNorthernSAMalleein2020 therewasaresponsetoalldeepripping treatments,howeverthemagnitudeofthe responsewasdependentonbothdepthand tynespacing(Figure4).
Ayieldbenefitof1.2t/hawasachievedby rippingtoadepthof45or60cmwithatyne spacingof05mThisyieldbenefitcouldbe maintainedataspacingof0.75cmonlyifthe soilwasrippedto60cmorwingswerefitted whenrippingat45cm.Allotherconfigurations leadtosmalleryieldbenefits,includingall treatmentwhichwererippedat1mrowspacing
Thistrialhighlightedthatachievingsoil looseningacrossthefullwidthdeepripperis requiredtomaximiseyieldbenefits
Ifdeeprippingtynesarespacedtoofarapart thenthesoilbetweenthetyneisnotloosened andthecropresponsewillnotbeuniformacross therippedarea.
Thiseffectcanoftenbeseeninpaddockswhere riplinesaredistinctiveinthecroporawavey patterncandevelopacrossthecrop(Figure5).
Inclusionplatesandorganic amendments
Insomeregions,farmersarekeentoenhance the benefits achieved by deep ripping by mixingtopsoilorotheramendmentsintothe soilprofileduringthedeeprippingprocess.
Toachievethisinclusionplatescanbefittedto thebackofthedeeprippingtynewhichopens avoidtoallowsurfacesoilandothermaterials tobeincorporatedatdepth.
In2021,atrialatYounghusbandevaluatedthe benefitsofusingdeeprippingtynesfittedwith inclusion plates to incorporate chicken litter whichwasspreadonthesoilsurface.
Inthetrialtheyieldofthecontroltreatment waspooratlessthan1t/haofbarley,however deeprippingaloneprovidedasignificantyield benefitofapproximately2t/ha(Figure6).
Addinginclusionplatesincreasedgrainyielda further0.4t/ha.Anadditional0.6-0.7t/haof barleywasgrownwherechickenlitterwas surfaceappliedandpassivelyincorporated withdeepripping,irrespectiveofweather inclusionplateswerefitted.
Figure4.Grainyieldforeachdepthxtynespacing combination Thecontroltreatmentyielded2072kg/ha whichisshownbythedottedline ErrorbarsrepresentLeast SignificantDifference.
Howeverthegreatestresponsestochicken littlerwasfromtheincorporationoftheorganic materialthrougheitherspadingoractivelyin injectingchickenlitterintotheinclusionplate duringtherippingprocess.Thereforethis researchshowedthatinthelowrainfallzone highlevelsofincorporationarerequiredto maximisethebenefitfromtheadditionof organicmaterial.
Page2
Figure5.Aerialphotographshowingthevisualcrop responsetotynespacingtreatmentsatWoodleighin2020.
Figure6 Barleyyieldfollowingdeeprippingandspading treatmentswithorwithoutorganicmaterial(chickenlitter@ 5t/ha)surfaceapplied Theinjectedtreatmenthadthe chickenlitterdirectlyappliedintotheinclusionplateduring therippingoperation.Errorbarsarethestandarderrorofthe means
Thepositionofthetineonthebaralso affectedtheseeddepth.Wheretynesatthe backoftheseedingbarworkexcessivelydeep, theymaythrowsoilontoadjacentrowssown withtinesfromthefrontofthebar
Thiswillincreasesthedepthatwhichthe seedsneedtoemergefromandmayalso carrypre-emergentherbicidesintotheseed row
Inthistrialseedsweregerminatingfrom75 mmdepthfromrowssownwiththefronttyne butonlyfrom45mmwhensownwithaback tineThiseffectresultedina16%decreasein wheatestablishmentandreducedearlyvigour ofthedeepsownrows.
Postrippingmanagement
Oneofthemajorchallengesincurredf deeprippingisthetrafficabilityofpad whichcanleadtoproblemssuchasp establishment,machinerydamagean somecircumstancessoilerosion. AtrialconductednearPinnarooin202 measuredtheeffecttwodifferentdeep (Figure8and9)androllingontrafficability, seeddepthandcropestablishment.Thetrial wassowncommerciallybythecollabora farmerusingaHorwoodBagshawPSSsys
Trafficabilitywasmeasuredbydrivinga Landcruiseruteacrossthesurfaceimmed priortoseedingandthenmeasuringthe oftherutsleftbythetyres
Un-rippedtreatmentshadshallowrutsof 50mmbutwere120mmfollowingdeepr withbothtypesofdeepripper(Figure10)
Consolidatingtherippedsurfacewitharo reducedrutdepthby50%Wheatseedsf un-rippedandrippedandrolledtreatme emergedfrom20-30mmdepthwhile unconsolidatedrippedtreatmentsemerg from50mmforthecurvedMicheltynean mmfortheTilcostraightlegtyne(Figure
Page3
Figure8.WilliamsonAgriripperfitterwithcurved Micheltynes
Figure9.HantonandSharradripperfittedwith straightshankedTilcotyne
Keyrecommendations
Severalopportunitieshavebeenhighlighted forfarmerstomaximisethebenefitsfrom deeprippingsandysoilsintheMalleeregion:
Ensurecompletesoillooseningacrossthe rippingzone:Rippingtynesneedtobe closeenoughtoensurecompletesoil looseningacrossthewidthofthedeep ripper Leavingsoilundisturbedbetween rippingwithdiminishtheyieldbenefit achievedbydeepripping.
Improverippingefficiencybyfitting wings:Wingcanincreasethezoneofsoil loosenedbytherippertyne Theycouldbe anefficientmethodofincreasingsoil looseningas50%moresoilwasloosened whilethecorrespondingincreasein droughtforcewasapproximately25%.
Organicamendmentsneedthorough incorporation:Materialssuchaschicken litterneedtobeincorporatedtomaximise itsbenefitinthelowrainfallzone. Theuse ofspadingoractiveinclusionwasmore effectivethanpassiveinclusionofsurface appliedchickenlitter.
Rollingpostrippingimprovestraffic ability:Rollingtoconsolidatethesoilcan aidinimprovingpostrippingtrafficability Consolidatingthesoilsurfaceisimportant tohelpmaintainseedingdepthand preventexcessivesoilthrowduring seeding.
Figure10.DepthoftherutmadebyaLandcrusiertyrefor eachtreatmentpriortoseeding Errorbarsarethe standarderrorofthemeans.
Figure11.Thedepthofseedlingemergenceforeach treatment.Errorbarsarethestandarderrorofthe means
Page4
The"DeeprippingtoenhanceproductiononMalleesoils"projecthasbeenhasbeensupportedbythe SouthAustralianGrainIndustryTrustanddeliveredbyprojectpartners: Disclaimer-ThisfactsheethasbeenpreparedingoodfaithbyMalleeSustainableFarming(MSF)onthebasisoftheinformationavailableto usatthedateofpublication,withoutanyindependentverification NeitherSAGITnoranycontributorrepresentthatthecontentsofthisfact sheetareaccurateorcomplete,nordoweacceptanyresponsibilityforanyerrorsoromissionsinthecontents,howevertheymayarise InvestigatingcompactioninasoilpitatWoodleigh -MSFCropWalkSeptember2021
