UnitedStatesRecoveryoffiDepartmentofAgricultureeResidTopsinNorthCent - PDF document

1 |,_{___UnitedStatesRecoveryoff._-_-.i_•"
|,_{___UnitedStatesRecoveryoff._-_-.i_•",_]DepartmentofAgriculture_:_:'_:eResid_TopsinNorthCentralForestExperimentSelectivelyCtStation.UResearchPaperNC-217p__,:_NorthernrHardwoodStandsJJamesA.Johnson,RodgerA.Arola,andEdwinS.Miyata\\. iioJohnson,JamesA.;Arola,RodgerA.;Miyata,EdwinS.Recoveryofresiduetopsinselectivelycutnorthernhardwoodstands.Res.Pap.NC-217.St.Paul,MN:U.S.DepartmentofAgriculture,ForestService,NorthCentralForestExperimentStation;1982.9p.Teststhefeasibilityandeconomicsofcompactinghardwoodtopswithaprototypeshearingandbunchingdevicepriortoskidding.Presentsproductivitylevelsandcostsassociatedwithcompacting,skidding,andchippinghardwoodtops.KEYWORDS:Loggingresidue,chipping,treedamage,productivity,.cost. oRECOVERYOFRESIDUETOPSINSELECTIVELYCUTNORTHERNHARDWOODSTANDSJamesA.Johnson,AssistantProfessor,..ForestResearch,FordForestryCenter,MichiganTechnologicalUniversity,L'Anse,Michigan,IRodgerA.Arola,PrincipalMechanicalEngineer,andEdwinS.Miyata,ResearchIndustrialEngineer,NorthCentralForestExperimentStation,Houghton,MichiganJ.Adeclininglandbase,anincreasingdemandforboomofacarriervehicle.Thespeciallydesignedforestproducts,plusenergyshortageshaveallcon-mountingmechanismbetweentheshearandboomtributedtoanincreasedincentivetobetterutilizepermitstheoperatortorotatetheshearassemblytoforestresidues.Forestresiduesincludetops,limbs,almostanyorientation.Thishighmaneuverabilityculltrees,andculllogs,aswellasotherunusedwoodmakesitpossibletoseverlargeprotrudinglimbsandnotdirectlyattributedtologgingoperationssuchasthenalignthemwiththebuttofthemainstemofthatfromtreesthatareinsect-infested,diseased,thetop.Oncealllargelimbsareseveredandaligned,wind-blown,orfire-damaged,thecompactedtopisskiddedtoawoodslandingforchipping.Itisestimatedthatslightlymorethan200milliondryton

2 sofwoodcanberecoveredannuallyfromTheexpe
sofwoodcanberecoveredannuallyfromTheexperimentaltopwoodshearingdevicewastheseforestresiduecategoriesonharvestedareasindesignedtoseverandbunchlimbsupto12inchestheeasternUnitedStates(Mattsonetal.1978).Re-indiameter.ThecarriervehiclewasaGafnerseriesgionally,63percentoftheseresiduesareintheSouthmini-skidder._Toallowforfastandefficientopera-and37percentintheNorth,andgenerically,68per-tion,wemodifiedthehydrauliccontrolsystemtocentarehardwoods.Withcurrentpracticesandcombinesevenmachinefunctionsintotwo_'joystick"equipment,chippingisthemostfeasibletechniquecontrolsplusonefootpedal.Theshearwasattachedforconvertingforestresidueintoausableform.Skid-totherear-mountedknuckleboombyarotatabledingentiretopswithlimbsintactisonepossiblecouplingmechanism.Thecarriervehiclewasse-approachtotopwoodrecovery.However,inselec-lectednotbecauseofitssuperiorsuitabilitybutrather'tive!ycutstands,rootsandbolesofresidualtreesbecauseofitsavailability.21maybedamagedexcessively(Dye1972,SteinhilbandDye1973).Damagemaybeespeciallysevereif,woodisrecovered,duringspringandearlysummer,whenthebarkisloose.Chippingtopswithlargecrownsisdifficultbecausetheydonotfeedwellintothechippei,._Mentionoftradenamesdoesnotconstituteen-ForestServiceScientistsdevelopedtheconceptofdorsementoftheproductsbytheUSDAForestServ-mechanicallycompactinglargehardwoodtopsintoice.aformmoresuitableforgrappleskidding(fig.1).2MemorandumofUnderstandingbetweenGafnerTheexperimentaltopwoodprocessingdevicetocom-Machine,Inc.,andNorthCentralForestExperimentpactthetopsisasmall,highlymaneuverable,hy-Station,U.S.DepartmentofAgriculture,ForestServ-draulicallyactuatedshearmountedonaknuckleice--April30,1976. P_innorthernhardwoodstands.SugarmapleandAmericanelmconstitutedthemajorspecieswithmi-norvolumesofbasswood,yellowbirch,redmaple,andhe

3 mlocktotaling149treesand116squarefeetofb
mlocktotaling149treesand116squarefeetofbasalareaperacrebeforeharvesting(figs.2,3).40BEFOREHARVEST(116SO.FT).o,oRECOMMENDED(85SQ.FT.)'......AFTERHARVEST(80SQ.FT.)=::30-O_-u,.co20-_.Q:"............................."JIIQ_%0IIIIIIII0610121416182022DIAMETERCLASS(INCHES)Figure2.--Topwoodstudy--treesperacrebydiam-eterclass(1977).=.c40BEFOREHARVEST(149/ACRE)ooRECOMMENDED(106/ACRE)•____AFTERHARVEST(119/ACRE)30-Figure1.Din-woodspreparationofhardwoodsaw-_timbertopsforharvesting(top)Typicalhardwoodc_.'sawlogtop(bottom)Compactedtop._:20-•OTHESTUDYAREA_"tu_.10-'The21-acrestudyareawaslocatedonMichigan__TechnologicalUniversitypropertyattheFordFor-.estryCenter,L'Anse,Michigan.Preharvestinven-toryofthisnorthernhardwoodstandindicated7,000oo618110112!141161181'2022board.feet(NetScribner)ofsawlogsand6cordsofpulpwoodperacre.Thesoil,classifiedasAllouez,DIAMETERCLASS(INCHES)wasawell-drained,coarsegravellyloam.Thetractwasonlevelterrainandwastraversedbyanall-Weatherroad.Previousselectiveloggingin1938andFigure3.DTopwoodstudy--basalareaperacreby1967hadremovedmostoftheculltreesoftenfounddiameterclass(1977).•2 In1977,1,800boardfeetofsawlogs(NetScribner)and5.1.tons(2cords)ofpulpwoodperacrewere.selectivelyharvested.Mostofthepulpwoodvolumecamefromtheupperstemportionsofsawlogtrees.Utilizationofupperstemwood,whichvariescon-siderablyfromoneloggingjobtoanother,dependslargelyontheavailabilityofapulpwoodmarketandonthedegreeofutilizationrequiredbythetimbersalecontract.Onthisparticularsiteinitialpulpwoodrecoveryfromtopswasabovenormal.Fifty-twopercentoftheinitialharvestedsawlog.,,-_.,_:,/7_',.____,_,"volumewassugarmaple,38percentAmericanelm,--',i(!_)i_i/i_I._'_"_"4percentbasswood,andtheremaining6percentj.-:,=.//_-_:-'_*_"madeup.ofyellowbirch,redmaple,andhemlock.Basalareawasreducedfrom116s

4 quarefeetto80squarefee_peracreintrees5in
quarefeetto80squarefee_peracreintrees5inchesd.b.h,andlarger.Ato_alof304treesweremarkedmakinganaverageof14.5treesperacre.Sixty-seventrees(22percent)werelessthan11inchesd.b.h.Theinitialharvestwasaconventionalshortlogsystemexceptthatpulpwood-sizedtreeswereskiddedtreelength.Theloggingcontractorwasnotawarethattopwoodhar-vestingwouldfollowtheloggingoperation.Theprincipalequipmentusedinthetopwoodhar-vestingrecoverytrialsweretheprototypeUSDAForestServiceshearingde_ice,aClarkRanger667GSGrappleSkidder,andaMorbark22-inchXLChiparvestorChipper(fig.4).Postloggingdamagetoresidualtreeswasassessedfollowingtheinitialconventionalselectivesawloghar.vestonseven1/5-acrestudyplots.Allfellingandskiddingdamagefromconventionalsawlogremovalwasidentifiedandrecorded.Aftertopwoodharvest-.-ing,alladditionaldamagewasidentifiedandre-cordedonthesamesevenplots.Eachdamagedtreewas.photographedsofuturerotprogressiondueto!oggingdamagecouldbeevaluated..Immediatelyafterfellingthetrees,thefollowingFigure4._Fieldtrialswithmechanizedtopwoodre-datawerecollected:species,diameter(d.b.h.),totalcovery:Compactingofresiduehardwoodtop(top);height,crownwidthandlength,andbuttdiameterGrappleskiddingofprocessedtop(center);andofthetopoutsidebark.CubicfootvolumeoftopstoConventionalchippingofprocessedtopwood(bot-a1.5-inchminimumdiameteroutsidebarkwasalsotom).determinedonSampletreesbycaliperingthemid-pointsOutsidebarkofsectionsrangingfrom1to8feetinlength(figs.5-7).Thesemeasuredtopswerekeptseparatefromtheunmeasuredtops.chippedandweighedseparately,socubicfoot/weightPriortoskidding,thetopwoodharvestershearedrelationscouldbedeveloped.Allsampletopswereandbunchedonlylimbsfromthelargercrowns.Small3 !1150.TOPVOLUME=142+0.00066TREEHEIGHTxD.B.H.=100_,4090_'"80I.z,.I...2::::)70__30tuLU602:=ZLu:::)50I_1,.j¢:O20_,40I-.

5 .¢1.OI.,.100,I,I,I,68101214161820222426D
.¢1.OI.,.100,I,I,I,68101214161820222426D.B.H.(INCHES)Figure5.--Topwoodvolumebydiameterclassandheight.S°L':-1.1o.,.,.o.,,'!I_40:::)30:E::)•_20OQ,O10-I.-,0,,IiI,I,IiI,I,.68101214161820222426D,B.H.(INCHES)Figure6._Topwoodvolumebydiameterclass(95percentconfidencelevel).100L|TOPVOLUME=13.8-3.43BUTTDIAMETER+0.3BUTTDIAMETER=80I,l,:::)60:E.:::),,,,IO40Q,.oI,.,200,I,IiIiIiIiI,46810121416182022BUTTDIAMETER(INCHES)Figure7.--Topwoodvolumebybuttdiameteroftop(95percentconfidencelevel).4 topswithnolarge,protrudinglimbswerenotproc-to1ton/top.Thisiscomparabletoearliertopwoodessedwiththetopwoodshear.Thetopswerethenrecoverystudies.3Theper-acreyieldonthestudyskiddedtotheroadside,areawouldhaveincreasedfrom6.8tonsto11.9tons/acre.AchipsampleanalysisindicatedamoistureAchainsawoperatorwasstationedatthelanding=contentofapproximately40percent(greenbasis).sitetoseveranyremaininglimbsorstubsthathin-Theprototypetopwoodharvesterwasusedtocutderedchipping.Thechipperhadagrapplewithlargeandbunch115tops.Inaddition,theoperatorarbi-teethweldedtotheoutside.Thisenabledtheoper-trarilydecidedthat40topsweretoosmalltoprocess.atortosplitlimbforksapartbyplacingtheclosedThemeasurementsofthetreeswereasfollows:grapplebetweenthemandthenopeningthegrapple.Topswerethenfedintothechipper.ChipswereblownProcessedSkippedintopilesandlaterhauledbyself-loadingvans.Totaltops(number)11540Twentytonsofchipscouldbeloadedinapproxi-D.b.h.oftrees(inches)18.713.2mately20minutes.Thevanswereweighedtode-Heightoftrees(feet)7968terminechipweight(greenweight).Topwidth(feet)2717Toplength(feet)3737TimeandmotionstudieswereperformedoneachD.o.b.ofbuttend(inches)13.49.1keyelementof-thetopwoodrecoveryoperationin-clUdingvehicletravelbetweentops.Fuelconsump-Processingofthe115topsrangedfrom1to7cuts/tion,numberofcutspertop,anddiame

6 terofseveredtop.Diametersofcutlimbsrange
terofseveredtop.Diametersofcutlimbsrangedfrom2to11incheslimbswerealsotallied.PerformanceoftheClarkwithanaverageof6.5inches(fig.8).Ranger667GSGrappleSkidderandMorbark22-inchXLChiparvestorwerealsotimestudiedtode-Topwoodharvesterdelayswereclassifiedintothreetermineproductivi,tyandoperatingcosts,groups:(1)unavoidable_thoseassociatedwithpro-duction,suchasoperatordecision-makingpriortoprocessing,cuttingsaplingsthatimpededtopwoodRESULTSANDDISCUSSIONprocessing,andrepositioningormovinglimbstoim-proveaccessibilitytocompleteatop;(2)mechani-Ofatotalof220chippedtops,137weresampledcal_thoseassociatedwithproductionusingapro-totypemachinesuchasproblemswiththecontrolsforvolume/weightrelations(greenweight).Theav-orshearblades,oilleaksfromlooseorpoorlypro-eragetopwas19.0cubicfeet,65.3lbs/ft3,and0.62tectedfittings,etc.,wouldnormallybeeliminatedintons(table1).The83unmeasuredtopswerealsotheproductionmachine;and(3)avoidable_thoseweighedwhichpermittedthecalculationofanes-relatedtotheprimemover,suchasliftingandlow-timatedcubicfootvolumebydividingbythesampleeringstabilizerpadsandclimbinginandoutofthe•weightof65.3lbs/ft3.Thiscalculatedto21.4ft3andtwoseatsrequiredtooperatethismachine.Lunch0.70tons/topforthe83unmeasuredtops.Thecom-andbreakswerenotincluded.Theaverageprocess-binedaverageforall220topswas19.9ft3and0.65ingtimepertopwasasfollows:t0ns/t0p.Thetotalweighton21acresamountedto285,700lbsor6.8tons/acre.Processingtime/topIfthe5itons/acreofpulpwoodinitiallyharvestedTimepertop(withoutdelays)(Minutes)'"4.1duringconventionallogginghadactuallybeenre-Unavoidabledelays.2coveredwiththetops,anadditional0.35tons/topMechanicaldelays.8wouldhavebeenrealizedandincreasedthetopweightAvoidabledelays.6Table1.'--TopwoodrecoveryweightsandvolumesTotal5.7NumberTotalTotalAverageAverageItshouldaga

7 inbenotedthattheprimemoverwas•oftopsvolu
inbenotedthattheprimemoverwas•oftopsvolumeweightvolume/topweight/topnotselectedbecauseitwasanidealmachinebutCuftLbsCuftTonsMeasuredtops1372,597,4'169,50018.960.62ratherbecauseofitsavailability.chippedUnmeaSuredtops831,780.6116,200,21.450.703UnitedStatesDepartmentofAgriculture,1976.chippedUnpublisheddatafromprototypeshearingdevelop-Total2204,378.0285.70019.900.65mentproject.U.S.DepartmentofAgriculture,Forest,Themeasuredtopweightpercubicfoot(65.3Ibs.)wasusedtocalculateService,NorthCentralForestExperimentStation,theunmeasuredtopvolume(1,4001bs/top65.31bs/cuft=21.4cuft/top).ForestrySciencesLaboratory,Houghton,Michigan.5 Ito,an in, s utt e"in L_JTOTALNUMBEROFTOPS:155whichlargerloadsoftopswerepiledatintermediate4o_"locationsalongtheserviceroadbeforeskiddingtheremainingdistancetothelanding.Thepurposeof"shuttle"skiddingwastosimulatetheproductivity30-,andcostsforatwoskiddersystem.Averageround_tripskiddingdistancewas1,700feetm828feetinr_thewoodsand872feetonskiddingroad.Skiddero_.20.productivitywasasfollows:_o..DirectShuttleI['--]_-_skiddingskidding4or--]r---qSkidderutilization(percent)7581012345e7Tops/load1.21.6CUTS/TOP(NO.).Tons/load(greenweight)0.841.12Tops/hour(withoutdelay)_8.921.1Tops/hour(withdelays)6.717.125[Tons/hour(withoutdelay,6.314.8•lgreenweight)_,20Tons/hour(withdelays,4.812.0.greenweight)_lS-ThestudywasexpectedtorunfromAugustthroughDecemberof1977;however,duetodelaysitwasznecessarytoextenditfurtherintothewinter.TherDlOzresultingsnowdepthsof30inchesormoreadversely•_affectedoperationefficiency.Itreducedperformancesbecausetheskidderhaddifficultymaintainingtrac-tion.Alsomanytopswerenearlycompletelycovered0withsnowandsomewerefrozentothegroundand2345678910"11neededtobebrokenfree.AnincreaseinproductivityBRANCHDIAMETER(INCHES)ofatleast10to20percentc

8 ouldlikelyhavebeenrealizedwithbettercond
ouldlikelyhavebeenrealizedwithbetterconditions.Figure8.mSummaryofnumber(top)andsize(bot-tom)oflimbssevered.Asshowninthefollowingtabulation,chipperutilizationwaslow:Becauseofthehighdegreeofutilizationintheconventionalharvestandresultingsmalltops,top-DirectShuttlewoodprocessorproductivitywaslow:skiddingskidding•.(Greentons/hr)Chipperutilization2532,Topwoodprocessor(percent)productivityWithoutdelays617.525.7(Tops/hr)(Greentons/hr)Withalldelays4.38.3Withoutdelays14.610.2Withunavoidabledelays11.78.2Withall.de!ays10.57.44Basedononeskidderoperating2.6daysinthewoodsandIdayontheroadtothelanding.Previousresiduestudies(MattsonandCarpenter5Workelementswere(1)reach,position,andgrap-1976)showedthatinsimilarstandsinwhichproductple;(2)liftandset;and(3)travel.Allotherelementsutilizationwasnotashigh,nearlyhalfoftheweightwereconsideredasdelaytime.ofharvestedtreeswasleftinthewoods.6Workelementswere(1)reach,position,andgrap-ple;(2)lift,swingandfeed;(3)chip;(4)blowontoTWOskiddingmethodsweretried:(1)directskid-thepileontheground.Allotherswereconsideredasdingofbothprocessedandunprocessedtopsfromthedelaytime.6 ThemainreasonforthelowchipperproductivitywasTable2.mSummaryofcostforharvestingthelimitedskiddercouldnotfeedittocapacity.Chip-hardwoodsawlogtopsperproductivitywasgreaterforshuttleskiddingthanfordirectskiddingbecauseofthelargerskidderloads.(In1980dollars)Thisallowedthechipperoperatortoincreasethesizeofgrappleloadswhenfeedingthechipper,thusre-Productioncost'ducingthedelaytimewaitingfortops:CostpertopCostpergreentonEquipmentShuttleDirectShuttleDirectEquipmentWithoutdelaysWithdelaysskiddingskiddingskiddingskidding(Minutes/ton)Topwoodprocessor2.372.373.393.39TopWoodprocessor5.98.1Skidder2.706.413.859.05SHUTTLESKIDDINGMETHODChipper1.752.57_2.503.67Skidder4.15.0Chainsaw0.21

9 0.210.300.30Chipper.2.'37.2Total7.0311.5
0.210.300.30Chipper.2.'37.2Total7.0311.5610.0416.41DIRECTSKIDDINGMETHOD'At100percentutilization(withoutdelay).Skidder"9.512.5Chipper3.414.0The22percenttotaldamagecomparescloselywithBecausetheexperimentalprocessingheadoftheatopwoodskiddingstudyconductedin1957inwhichtopwoodharvesterwasunabletoseveralllimbsclose21percentofthetrees5inchesd.b.h,andlargertothemainstem,someoftheremaininglimbstubssustainedinjury(Hooker1957).hadtobecutbeforethemainstemcouldbefedintothechipper.Althoughthiswasnottimeconsuming,Hesterberg(1957)determinedthatwoundwidthitresultedinaddedchipperdelay.Thechainsawandwoundsurfaceareaarethebestindicatorsofcostatthelandingwas$0.30pergreenton.Anim-theseverityofloggingdamage.Hefoundthat50.provedtop.woodprocessorheadshouldbecapableofpercentofthewounds150squareinchesorgreaterremovinglimbsclosertothemainstemandprecludeshowdecayattheendof10years.Stemwoundstheneedtotrimshortstubs,thuseliminatingamanexposedformorethan20yearshada50percentatthelanding.Incomparingcosts,theskidderop-frequencyofdecaywhenmorethan60squareincheseration.hadthehighestcostpertonandpertop,ofsapwoodwasexposed,and80to100percentfre-amountingto$3.85(shuttle'skidding)and$9.05(di-quencyofdecaywhen130squareinchesormorerectskidding)pergreenton(table2).Totalproduc-wereexposed.Hefurtherconcludedthat92percenttioncost,excludingtransportation,rangedbetweenofthedecaycouldbeexplainedbytheoriginalwoundwidth.Morethan50percentofthestemwoundsabout$10.00to$16.50pergreentondependingonskiddingmethodused.Thereaderiscautionedthatshowdecaywithin10yearswhenloggingscarsarethesecostsshouldbetemperedbythefactthattheymorethan7incheswide.Fora20-year-oldinjury,50percentshowdecaywhentheyare4to7inchesaretheresultofasinglecasestudywithanexper-imentalmachine,wideand100percentshowdecaywhenthewound'is7inchesw

10 ideorwider.Becausefewoftheinjuriesexceed
ideorwider.Becausefewoftheinjuriesexceeded50squareinchessurfacearea,wearbi-RESIDUALTREEDAMAGEtrarilydividedtheinjuriesaseithermedium(26squareinchesormoreofcambiumorwoodexposed)orlight(lessthan26squareinchesofcambiumor•Damagetotheresidualtreeswasasfollows:woodexposed).Eighty-threepercentofthebolein-DamagecategoryDamagetreesjuriesduetoconventionalskiddingwereclassified(No./acre)(Percent)as"light"and17percentas"medium."Topwoodskid-CONVENTIONALLOGGINGdingresultedin75percent"light"and25percentFelling4.34"medium"injuries.Measurablerootinjuriesoc-Skidding'12.911curredonlyduringtheconventionalloggingphaseTotal17.215oftheharvestwhichwasconductedduringthesum-TOPWOODSKIDDINGmer.Topwoodharvestingwasconductedonsnow-Additionaltreesdamaged5.04coveredground,thuseliminatingadditionalrootAdditionaldamagetodamage.Ofthoserootsdamagedbyconventionalpreviouslydamagedtrees3.63skidding,90percentwere"light"and10percentwereTotal8.67"medium."o7 Theinjurylevelrecordedinthisstudyappearstotionalwhole-treechippingofpulpwood-sizedtreesbeacceptablebecausenoneofthedamagewasse-andconsequentlyrequiresskilledoperators.vere.Themajorityofthewoundsexposedlessthan50squareinchesofsapwood.BasedonHesterberg'sSawtimberoperationstypicallyleavelargetopswork,weexpectmostofthesmallerwoundstohealfromwhichpulpwoodstickshavenotbeenremoved.overwithoutcausingsignificantamountsofrot.Also,Thisaddedtoplengthfacilitatesfeedingintothesomeofthemoreseriouslydamagedtreeswillprob-chipperbecauseitgivesthechipperfeedrollssome-thingtoengagetogetthetopstarted.Itmaybeablybeharvestedbeforemajordecayoccurs.desirabletoleavethepulpwoodsticksinothertypesTheioggi.ngcontractor'sawarenessoftheimpor-oflogging,too,iftopwoodistobesalvaged.tanceofminimizingdamagecancontributesignifi-cantlytomaintainingqualityresidualtrees.Fort

11 hisstudy,achainsawoperatorwasstationedat
hisstudy,achainsawoperatorwasstationedatthechipperatalltimestomakeanynecessarycutsonthetopssotheycouldbechipped.Becausethisoperatorwasutilizedonly13percentofhistime,CONCLUSIONSANDitmighthavebeenmoreefficienttohavethechipperRECOMMENDATIONSoperatoralsodothechainsawwork.Anotheralter-nativewouldbetoreplacethechippergrapplewithJBecauseoflowyieldsandthenecessityofahighlyagrapplethatutilizesahydraulicallyactuatedchainmechanizedsystem,thefeasibilityofanytopwoodsawbuiltwithinthegrappleandcontrolledbytherecoverysystemwilldependheavilyoneconomicchipperoperator.Animprovedtopwoodprocessorandmarketconditions.Thisuniquefieldtrialeval-shouldbecapableofseveringlimbsclosertotheuatedthepotentialandidentifiedvariousproblems,mainstemtherebyeliminatingtheneedtodoanymanyofwhichCouldbeeliminated.Thisapproachchainsawing.torecoveringtopwoodisonlyoneofseveralpossibleapproaches."Anotherapproachistouseatopwoodharvesteroutfittedwithbunkskiddingcapabilities.Thisbasic.Ofthe155topsinthetopwoodharvesterplot,115typeofmachineisalreadyavailableandistypicallywerecompactedbythetopwoodharvesterand40equippedwithaloaderandinvertedgrappleonthewereskiddedas_is,becauseofanarbitrarydecisioncarrierbed.Iftheloaderwereadaptedwithatop-thattheycouldbeskiddedintactwithoutcausingwoodprocessinghead,asinglevehiclecouldreducesevereresidualstanddamage.Afterobservingthetopsaswellasloadandskidtheprocessedtops.residualstanddamage,itappearsthatthesefigurescouldlikelyhavebeenreversed--40compactedandThisstudyhasdemonstratedthepotentialofre-ll5skipped.Insomeinstancesitwaseasiertoskidcoveringtopsthroughcompactionwithoutgreatlyuncuttopsbecausetheshort,crookedpiecesofthedamagingtheresidualstand.Harvestingduringthecuttopsslippedoutofthegrapplewhentheloadspringorearlysummer,whenbarkisslipping,wouldshifted.Askidderw

12 ithaconstantpressuregrapplemostcertainly
ithaconstantpressuregrapplemostcertainlyincreasedamage.Standswithmanyshouldlessenthisproblem,pole-sizedtrees(5to9inchesd.b.h.)wouldprobablymakeharvestingmoredifficultandalsoresultin'Amajorconsiderationishowtoincreasethesizeincreaseddamagetotheresiduals.ofskidderpayloads.Althoughtwomethodsweretried.inthisstudy,neitherwassatisfactory.Achokerskid-Thisstudyhasdocumentedthetopwoodvolumesdermayprovemoreproductivethanagrapple,pri-thatmightberecoveredfromselectivelycutnorth-marilybecauseseveraltopscouldbecollectedintheernhardwoods.IflowqualitytreeswereharvestedwoodsalongWithlargelimbs,thuseliminatingdou-alongwiththetops,volumesperacrewouldincreaseblehandliffg.Atthelandingthetopsandlimbscouldandtheeconomicpicturewouldbeevenmoreat-bebuckedintohighestvalueproductswiththesmalltractive.Asthedemandforwhole-treechipsin-brancheschippedandthelogssetasidefortransportcreasesandthevalueofchipsforfuelbecomesmoretothesawmill,attractive,topwoodharvestingwillbeofgreaterim-•portance.ItisintheinterestoftheforestindustryThiswasaone-of-a-kindstudywithnochancetothatgoodsoundproductionandcostfiguresareimproveoperatorskill.Skilledoperatorsobviouslyavailableforharvestingloggingresidues.wouldincreaseproductivityandoverallefficiencyofanyloggingOperation.ThehandlingandchippingTheresultsofthisuniqueapproachestablishofsawlogtopwoodismoredifficultthanconven-baselinedataforonemethodofrecoveringtopsando8 limbs.Weknowofnootherattempttorecovertop-Hesterberg,GeneA.Deteriorationofsugarmaplewoodbythismethod,andatthistimeweneitherfollowingloggingdamageStn.Pap.51.St.Paul,recommendnordisapproveoftheapproach.Cer-MN:U.S.DepartmentofAgriculture,ForestServ-tainlyotherapproachesexistandtheseshouldbeice,LakeStatesForestExperimentStation;1957.researchedanddocumented.Hopefully,afterinves-58p.tigatingse

13 veralapproaches,aneconomicallyfeasi-Hook
veralapproaches,aneconomicallyfeasi-Hooker,Leland.Utilizationofhardwoodloggingres-blemethodwillresult,idue.ThePaperIndustry1957(11)"689-691;1957.Mattson,JamesA.;Carpenter,EugeneM.LoggingThesedatamaybeconsideredaslowerlimitsofresidueinanorthernhardwoodtimbersale.North.whatcouldbeaccomplished.AsmoreislearnedaboutLoggerandTimberProcessor24(7):16-17,29;1976.organizingtopwoodharvestingjobsandasoperatorsMattson,JamesA.;Bradley,DennisP.;Carpenter,becomemoreexperienced,productivityandcostra-EugeneM.;Winsauer,SharonA.;Hahn,Geraldtiosshouldimprove.T.Forestresiduesenergyprogram--finalreport.l.ContracttoERDA,ContractNumberE-(49-26)-1045.U.S.DepartmentofEnergyReportTID-28416.St.Paul,MN"U.S.DepartmentofAg-,LITERATURECITEDriculture,ForestService,NorthCentralForestExperimentStation;1978.297p.Dye,GlennW.Harvestinghardwoodloggingresi-Steinhilb,H.M.;Dye,GlennW.Harvestingloggingdues:anoperationsandcostanalysis.Hough-residuefromaselectivelycutnorthernhardwoodton:MichiganTechnologicalUniversity;1972.106stand.North.LoggerandTimberProcessor21(11):p.Master'sThesis.12-14,34-37;1973.U.S.GOVERNMENTPRINTINGOFFICE:I982-665-451/162°9I 0•NorthCentralForestExperimentStationForestService--U.S.DepartmentofAgriculture1992FolwellAvenueSt.Paul,Minnesota55108ManuscriptapprovedforpublicationApril20,19821982 o-ErrataSheetforResearchPaperNC-217.,•'"ERRATASHEETBEFOREHARVEST(149/ACRE)_C_'_RECOMMENDED(10S/ACRE),.--'---AFTERHARVEST(119/ACRE)iLli,x12oH"•_')'loi0--II:.I.I1l1_l__06810121416182022•DIAMETERCLASS(INCHES)Figure2.--Topwoodstudy--treesperacrebydiam-eterclass(1977).}40,,,o=.........BEFOREHARVEST(116SQ.FT)CORECOMMENDED(85SO.FT.)......AFTERHARVEST(80SO.FT.)_o-O.okd2o-•In_-,,_10-.0IIILAIt.,O6II10121410182"022DIAMETERC'LAII(INCHES)Figure3.--Topwoodstudy--basalareaperacrebydiameterclass(197