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Jeff Olsen, Extension horticulturist, Yamhill County; original author Robert L. Stebbins, Extension horticulture specialist emeritus, tree fruit and nut crops; both of Oregon State University.
Training and Pruning Your Home OrchardJeff Olsen
PNW 400 • Revised July 2011
A Pacific Northwest Extension PublicationOregon State University • University of Idaho • Washington State University
The BasicsWhy train fruit trees?• Trainingdevelopsastrongtree
structurethatcansupportheavycropswithoutlimbbreakage.
• Traininghelpsbringayoungtreeintoproductionatanearlyage.
Why prune fruit and nut trees?• Pruningreducesoveralltreesize.• Pruningmakestreeseasierto
sprayandharvest.• Pruningyoungtreescan
improvestructuralstrengthandinducebranching.
• Pruningmaturetreescanincreasetheirproductionandimprovefruitquality.
• Pruningreducestheneedtopropupfruit-ladenbranches.
Basic terminologyBranch collar—Theraisedtissueatthebaseofevery
branch.Itcontainsspecializedcellsthatsealoffpruningwoundsfromwoodrotfungi.
Crotch angle—Theangleformedbetweenthetrunkandalimb.Thestrongestcrotchangleis45to60 degrees.
Crown—Thebaseofthetrunkwherethetreemeetsthesoil.
Heading (orhead cut)—Apruningcutthatremovesonlypartofabranch.
Lateral branch—Asideshootoffofanotherbranch,usuallyatamorehorizontalangle.
Leader—Theuppermostportionofascaffoldlimb.Inacentral-leadertrainedtree,onlyoneleaderisleftinthecenterofthetree.Multiple-leadertrainedtreesusuallyhavethreetofiveleaderspertree.
Scaffold limb—Alargelimbthatformsatree’sframework.
Shoot—Thelengthofbranchgrowthinoneseason.Thebudscalescars(ringofsmallridges)onabranchmarkthestartofaseason’sgrowth.
Spur—Ashortshootthatfruits.
Figure 1. Common terms used in pruning and training fruit trees.
Leader
Water sprout
Secondary scaffold
Scaffold limb
CrotchSucker sproutTrunk
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Stub—Ashortportionofabranchleftafterapruningcut.Avoidleavingstubs.
Sucker sprout—A1-year-oldshootthatgrowsfromtheroot.
Terminal—Theendofanyshoot.Thinning cut—Apruningcutthatremovesanentire
branchfromitspointoforigin.Vertical branch—Abranchthatgrowsupright.Water sprout—A1-year-oldshootthatgrowswithin
thetree.
Save the branch collar, and don’t use wound dressings.
Prunesothatyoudon’tleaveastub(figure2),andalsosothatyoudon’tmakeawoundlargerthannecessary(asoccurswitha“flushcut”).Cutjustoutsidethebranchcollar(theraisedtissueatthebaseofeverybranch).Itsspecializedcellssealoffpruningwoundsfromwoodrotfungi.
There’snoclearevidencethatwounddressingsreducewoodrotsinpruningwounds.Earlytreetraininghelpsyouavoidlargepruningwoundslowinthetree,whichmightbecomeinfected.
General rules for training• Starttrainingatplantingtime.• Removeunwantedshootsinsummerwhen
they’resmall.• Trainmorebylimbpositioningthanbypruning.• Followthetrainingprogramconsistently,asoften
asnecessary,sothatyoucompletepropertrainingassoonaspossible.
Manage your fruit trees activelyThebestwaysforhomeownerstocontrol
theheightofafruittreearetoplantadwarfingrootstock,prunewell,oruseatrellissystem.Keepingthetree’sheightlowallowsforeasierharvestingandpestmanagement.Asahomeowner,youmayhaveinheritedfruittreesonyourpropertyfrompreviousowners.Youcaneitherchoosetomanagethemorreplacethemwithavariety,rootstock,ortrainingsystemthatcontrolstheoverallheightofthetree.Apost-and-wiretrellissystemisapopularwaytokeepfruittreesatamanageableheight(see“Espaliertraining,”page5).
Untendedfruittreescanbecomeinfestationsitesforseriousinsectanddiseasepests.Untendedtreescanmakeitdifficultforcommercialgrowersintheregiontocontrolkeypests.Ifyouareusinganuntendedfruittreemostlyforshade,perhapsyoushouldreplaceitwithanonfruitingshadetree.
General rules for pruning• Pruneallfruitandnuttreesatplantingtimeto
balancethetopswiththeroots.You’llneedmuchlesspruningatplantingifyouplantoirrigatetheyoungtreefrequentlyduringitsestablishment.
• Pruneyoungtreesverylightly.• Prunematuretreesmoreheavily,especiallyif
they’veshownlittlegrowth.• Prunethetopportionofthetreemoreheavily
thanthelowerportion.• Prunewhenalldangerfromfallorearlywinter
freezehaspassed,butbeforefullbloominspring.SweetcherrytreesmaybeprunedinAugustwhenthere’slessdangerofbacterialinfection.
• Inamaturetree,thinoutmoreoftheshootsthatgrowtowardtheendofawell-prunedbranch.Thisincreasesfruitsizeandqualityontheremainingshoots(figure3,page3).
Branch collar
Pruning cut
Branch bark ridge
Figure 2. Always preserve the branch collar, the raised tissue at the base of every branch. The branch collar contains specialized cells that allow a tree to seal off pruning wounds and prevent rot from damaging the branch’s heartwood.
Make your pruning cut at an equal and opposite angle from the branch bark ridge.
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• Toreducetheheightofatreethat’stootall,cutlimbsatthetopofthetreetoalateralbranchthatistheheightyoudesire(figure4).Leavethebranchcollarbutdon’tleavestubs.Stubswon’thealandcouldbeastartingpointforwoodrotfungi.
• Thinningoutandheadingback(figure11,page 7).Thinningoutresultsinlong,flexiblelimbsthatbenddownwhenloadedwithfruit.Headingbackcauseslimbstobranchlaterallyandstiffen.Lightheadingstimulatesbranchingwhenyoutrainyoungtrees.
• Bendnearlyverticallimbs45to60degreesfromverticaltostimulatefruitproductionearlierinthelifeofthetree.Bendlimbstothedesiredangleandsecuretheminplacebyusingweights,tyingthemwithtwine,orusingnotchedlimbspreadersinthecrotchofthebranch.Keepthebentlimbinthedesiredpositionforonegrowingseasontoallowthebranchtostiffenandstayatthatangle.Takecaretobendbutnotbreakthebranch.Thethickerandmoreuprightalimbis,themorebenefititreceivesfrombending.Bendinghelpskeepatreesmallandmanageablebychannelingthetree’sresourcesintofruitinsteadofshootgrowth.
Figure 3. On this well-pruned branch, thin out more shoots toward the end (gray).
Figure 4. This tree is too tall. To reduce its height, cut out whole limbs at the top (gray).
Tree training systemsOpen center training (figure5, page 4).
Choosethreeorfourshootstoformmainscaffoldbranchesthefirstwinter.Removeothershootsthatmightformcompetinglimbs.Or,headthembyremovingone-fourthtoone-thirdoftheirlengthifthey’relongandnotbranched.
Whenyouremovelargelimbs,firstcutpartwaythroughthebranchontheunderside,thenmakethetopcut.Don’tleavestubs.
Tokeepatreesmall,prunemoderatelyeveryyearanddon’tapplyalotoffertilizer,manure,orcompost.
Central-leader training (figure 6, page 4). Ifanurserytreehasfewornobranches
atplanting,headitat24to30inchesaboveground.Totraintreestoacentralleader,chooseavigorousshootnearthecenterofthetreeafterplanting.
Duringspringorearlysummer,removeshootsneartheleaderthatwillcompetewithit(becauseoftheiruprightaspectandvigor)
(Continued page 5)
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Figure 5. It takes four winters to train trees to an open center (gray indicates removed or headed shoots). A: The first winter, choose three or four shoots to form main scaffold branches. Remove or severely
head all others. Scaffold branches should be at least 8 inches apart on the trunk for a strong tree structure.
B: The second winter, choose one or two more. C: By the third winter, scaffold selection should be complete. D: The fourth winter shows a good open center. Four main scaffold limbs evenly distributed around
the trunk are enough; a fifth limb crowds.
Figure 6. It takes four winters to train trees to a central leader (gray indicates removed or headed shoots). A: The first winter after planting, choose a vigorous shoot high on the tree. Cut off the top to stimulate
branching if it’s 2 feet long or longer. Head all other vigorous shoots more severely. B, C, and D: Repeat the process the following three winters so that no side branches
become vigorous enough to compete with the central leader.
B C DA
B C DA
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(figure 7).Inthedormantseason,headtheleaderbyone-third,andtiedownorremovecompetingshoots.
Eachyear,spreadlimbsthataretooupright(figure8).Repeattheprocessinthefollowingtwoseasonssothatnosidebranchesbecomevigorousenoughtocompetewiththecentralleader.
Somedwarfapplevarieties(suchasLiberty,showninfigure6,page4)havewide-angledlimbsnaturallyanddon’tneedheadingorspreadingifthey’resupported.Delicious,Newton,andothervarietieswithnarrowcrotchesoruprightlimbs—orboth—dorequirespreading.Thecentralleadersofnon-supportedtreesneedannualheadingtodevelopshort,stoutlimbs.
Modified central-leader training Amodifiedcentral-leadertraining
systemfollowsthesamestepsdescribedforcentral-leadertraining(figure6).Thecentralleadercausesthelateralbranches’anglesoffthetrunktobewider,whichincreasesthecrotchstrengthandhelpsinduceearlyfruitproduction.Onceyou’vechosenandestablishedthemainscaffoldbranches(figure1,page1),thecentralleaderisnolongernecessary.Youcanremovethe
centralleaderinthethirdorfourthyearofgrowth.Now,you’llbetrainingthetreetoamultiple-leadersystem.
Espalier trainingEspaliertrainingdevelopstreesintwodimensions
only.Inahomegarden,youmightuseittosavespaceandtoenhancetheaestheticappealofyourfruittrees.Italsocreatesatreeformthatiseasiertopick,prune,andspraythoroughlyforpests.
Youcangrowdwarfappletreesonapostandwiretrellisinahedgerow.Postsmayextendfrom6to10 feetabovetheground.Treatedpostsarebest,butsound,untreated4x4cedarpostsmayworkwell.Anchortheendpostsagainstanotherpostdrivenseveralfeetintoundisturbedsoilatanopposingangle.
Figure 7. The highest portion of a scaffold limb is called the leader. Thin it to an upright side shoot. Head that shoot and remove all upright shoots that might compete. To avoid overgrowth in the tree top, repeat this process annually.
Before
After
Figure 8. While the tree is young, spread branches that make very narrow angles with the main trunk. If these limbs are allowed to grow to a productive age without being spread, they usually break away from the trunk, often splitting the entire tree.
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Usegalvanizedwire,12-gaugeorheavier.Thelowestwireshouldbeabout4feetabovetheground,withhigherwiresat2-footintervals.Tiethemaintrunktothesewires,usingaloopbigenoughtoallowthetrunktogrowwithoutbeinggirdled.Ifyouattachthetrunktothetrelliswirewith5⁄8-inchboxstaples,itwillgrafttothewireandnotgirdle.
Ifyouuseindividualpostsateachtree,makesuretheyextendatleast6feetabovetheground,anddriveorsinkthematleast2feetintotheground.Woodentreestakesshouldbe2inchesormoreindiameter.
Whentrainingthetree,selectbudstoformthebranchesattheproperheightandcutoffthetreejustabovethem.Asthesebudsgrow—andbeforethey’veproducedenoughwoodtobecomestiff—fastentheshootsthatgrowfromthemtotrainingwiresorstickswithmaskingtapeorothersuitablematerial(figure9).
Palmetteisaspecificpatternofespaliertraining.Developthelowestbranchesfirst,anglingthematabout30degreesatthestart.Widenthisto45–50 degreeswhenthey’reaslongasyouwantthem(figure10).
Headthecentralleaderjustabovewhereyouwantbranches,anddeveloponeortwohigherpairsofbranches,keepingthemshorterandslightlymorespreadingthanthelowerpair.It’sbesttohaveatleast18inchesverticallybetweenbranches.
Fruiting habitsFigure12(page7)shows
thedifferenceinfruitinghabitbetweenpeachandapple.Peachesbloomonlyon1-year-oldwood;applesusuallybloomonspursorshootsfrom2-year-oldwood.Figure13(page7)showsamatureappletree’sfruitspurs,whichbearthefruitcrop.Cherries,plums,pears,andapplesallproducetheirfruitonspurs.
Spursrequiregoodlightexposureinordertobefruitful.Thinningcutsthatopenupthetreetolightpenetrationhelptokeepfruitfulspursthroughoutthetreecanopy.
Pruning toolsLong-handledpruningshears(figure14,center;
page8)arethemostusefultoolforalmostallpruningjobs.
Handshears(figure14,bottom)areusefulfortrainingyoungtrees.
Ifyouneedtomakelargecuts,useapruningsaw(figure14,upperleft).
Ifyoumustusealadder,useonlyasturdystepladder.Setitfirmlyonthegroundtopreventaccidents.
Figure 9. Espalier training.
Figure 10. Palmette training.
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Applying the basicsFruit treesApple Fully dwarf trees
Youmustsupportfullydwarftrees,orthey’llbendtothegroundundertheweightoftheirfruit.Youcanuseindividualstakeswitheachtreeorbuildatrellissupportsystem(see“Espaliertraining,”page5).
Trainingfullydwarfappletreestoacentralleadersupportedwithapostortrellis(figure6,page4)canproducehighlyproductive6-to10-foottrees.Thissystemhelpsavoidbush-liketreesonly4or5feettallthatarebentdownwiththeweightoftheirfruit.
Inthespringfollowingplanting,whenshootsare3 to4incheslong,selecttheuppermostvigorousshootandremoveothershootsnearit.Returnseveraltimesinsummerandremoveortiedownanyshootsthatcouldcompetewiththeleadshootbecauseoftheiruprightaspectandvigor.Headtheleadshootbyathirdinthedormantseason.
Keepthreetofivebranchesthatare18to30inchesabovegroundtoformabasicsetof
permanentbranches.Ifthey’reupright,tieorweighthemdowntonearlyhorizontal.Positionhigherlimbstobelowhorizontaltoreducetheirvigorrelativetothepermanentbasicset.
Semi-dwarf treesYoucantrainasemi-dwarftreetoacentralleader
ordevelopitasamultipleleadertree,dependingonthetree’svigor.Centralleadertrainingisbestforweak-growingvarietiesonpoorsoil.Trainvigorousvarietieswithmultipleleaders(threeorfourleadbranches)(whentrainedtocentralleaders,theymaybecometootall).Whenthey’re4to6 incheslong,
Figure 11. Thinning out (left) and heading back or “stubbing” (right).
Figure 12. One-year-old wood is the wood that grew during the previous summer: peach (left), apple (right).
Figure 13. The fruit spurs on a mature apple tree bear the fruit crop.
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spreadtheseshootsusingcocktail-styletoothpicksorspring-typeclothespinsplacedinthecrotchesofthebranches.Onawindysite,supportthetreewithasturdystakeforthefirst10years.
Inthefollowingyears,spreadortieouttheleadlimbstoabout30degreesfromvertical.Weighdownthesidelimbsthatarisefromtheseorspreadthemtohorizontaltostimulateearlyproduction.Asthetreebeginstobearfruit,limbsmayrequireproppingortyingtopreventbreakage.
“Spur type” treesThistypeofappletreeformsmanysmallspurs
onyounggrowthratherthantheusuallongshootsandleafbuds(figure15).Thisishowitgotitsname.Becausethesetreesfruitatayoungageandaresmallerthanstandardstrainsofthesamevariety,theymakeidealhomeorchardtrees.
Eachspurbearsaflowercluster.Theleavesareclosetogether,thetreebranchesarelessfrequent,andthetreegrowsslowly.
Spurtypetreesareavailableonbothvigorousanddwarfingrootstocks.Ifyougrowthemonvigorous
rootstocks,theymaynotrequireartificialsupportuntiltheyareinproduction.
Becausetheybranchsparsely,leavemorebranchesinaspurtypethaninatreeofstandardgrowthhabit.Totrainthemtoacentralleader,spacethelowersetoflimbsseveralinchesapartverticallyontheleader,andreducetheirnumbertofourorfive(figure6,page4).
Standard trees (full size trees on seedling rootstocks)
Fruittreesonseedlingrootstocksareexcessivelyvigorous,sotheyarenotassuitableforhomeorchardsastreesongrowth-controllingrootstocks.Ifyouchoosetouseaseedlingrootstock,cutbackthenewlyplantedtreesto24to30 inchesfromtheground.Trainthemtothemodifiedcentral-leadersystem(seepage 5).
Figure 14. Pruning saw (upper left), long-handled pruning shears (center), hand shears (bottom).
Figure 15. On this central leader of a 2-year-old, spur-type Delicious apple strain, notice the many short spurs with blossom clusters. Extensive fruit thinning is required to allow this tree to grow and ripen the remaining fruit.
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It’sbesttohaveonlyfourmainscaffoldlimbs,spacedequallyaroundthetrunkandverticallyseveralinchesapart.Developthemainscaffoldlimbstojustafewdegreesabovehorizontal.Makesurethatallsecondarybranchesalsohaveagradualupwardaspect(figure5,page4).
Thebranchesofamature,non-dwarfappletreemayspreadover40feetindiameterandreachaheightof30or40 feet.Pruneregularlyandtiedownuprightlimbsinthetoptomaintainaheightof12to15feet.
Prunetomakethelowestlimbsthemostvigorousandproductiveinthetree(figure 16).Shorten,thinout,andbenddowntheupperlimbstoaccomplishthis.Removerisers(thesegrowstraightup)andhangers(thesegrowstraightdown)fromthepermanentlimbstoopenaverticalspaceofabout3 feetbetweenthelowestlimbsandthoseabove,sothatlightcanpenetrate.
Pear Initialresearchshowspromiseforgrowing
pearsonatrellis,butmostcommercialpearsinthePacificNorthwestaregrownwithacentralleaderormodifiedcentral-leadertrainingsystem.Ifyoufeeladventurous,youcantrygrowingtrellisedpears.Thefollowingrecommendationsdescribethestandardwaytotrainpeartrees.
Headpeartreesatabout24inchesatplanting.Ifthetopisbranched,keepthreeorfourbranchesasleaders.Selecttheseleadersearlyinthefirstsummerandspreadthem.Dolittleornopruningexcepttoheadandspreadtheleadersannuallyuntilthetreestartstobear.
Don’theadsidebranches.Headingwouldmaintaintheiruprightposition.Spreadorweightallvigorousshootsexcepttheleadshoots.
Openladderbaysbetweenscaffoldlimbsofmaturetrees,andregularlyreducetreeheighttowhatyoucanreachfromyourladder.Shortenorremoveupperlimbssotheydon’tshadethelowerlimbs.Thinoutthebranchesofmaturetrees,anddotheheaviestpruninginthetop.
Removelongshootsinthecenterandtop,butleavesomeshortshootsandmostspurs.Removehorizontalbranchesinthetopsotheywon’tproducesuckers.
Invigorateslow-growingspursystemsbycuttingthembacktoabouthalftheirlength,orremovethemandreplacethemwithnewshoots.OnAnjouandComicevarieties,cutbackmostofthespursystemsandsomeshootstoincreasefruitsize.
Figure 16. (Above) This old seedling-rooted apple tree is maintained at a height of about 12 feet by extending the branches horizontally, rather than vertically. (Below) This enlarged view shows how the slightly upward aspect of the entire main limb and the terminal part of the side limbs maintain a good balance between shoot growth and fruiting. Pruning consists of many small thinning cuts.
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Sweet cherry Atplanting,headnurserytreesattheheightyou
desireforscaffoldbranches.Trainsweetcherrytreestotheopencentersystem(figure5,page4)withthreetofivescaffoldbranches.Youngsweetcherrytreesoftengrowverticallimbs6to8feetwithoutbranching.Youmustheadthemtoinducelateralbranchformation.
Pruneinsummertoreducethere-growthofvigoroustrees.Ifayoungtreeisgrowingveryrapidly,cutoffafootormoreofnewgrowthafterabout3feetofgrowthhasbeenmadeinthesummer.Thiswillcausebranching.Youcanhastenproductionbytyingdownorweightinglimbstohorizontal.
Topromotebranchingontreesnotprunedinsummer,headeveryshootinwintertoabout2 feet.After5or6years,stopheadingandthinoutcrowdedbranches.
Bacterialcanker,acommondiseaseofcherrytrees,frequentlycausesgumminganddeadareasor“cankers”onlimbs.Ifitinfectsthecrownortrunk,itcankillthetree.Ifagummy,deadareaencirclesmostofalimb,youmustcutoffthelimb.
Bacterialinfectioncanenterthroughpruningwounds.Toavoidthis,pruneinAugust.Youusuallycanavoiddeathfrombacterialcankerbybuddingorgraftingavarietyaboutafootoutontherootstocklimbs.
Maturetreesrequirelittlepruningexceptasneededtoreducetreeheight.Ifbirdsareeatingalotofthefruit,youmaywanttonetthetree.
Sour cherry Sourcherrywoodisquitebrittle,sogivespecial
attentiontodevelopingwide-angledcrotchesinyoungtrees.Eitherselectwide-angledshootstoformlimbs,orspreadshootstowidentheangles.Threemainscaffoldlimbsareenoughforasourcherrytree.Themodifiedcentral-leadersystemhelpsformwide-angledscaffoldlimbswithouthavingtospreadthem.
Inthefirstandsecondsummers,removeexcessshootssothatallnewgrowthisonthepermanentscaffoldlimbs.Inmaturetrees,onlyoccasionalthinningoutofexcessbranchesisneededtokeepagoodbalanceoflightandfruitfulnessthroughoutthetree.
Peach Cutoffpeachtreesabout12to20inchesabove
thegroundatplanting.Traintreestotheopencenterorvasetypesystem(figure5,page4).Developnomorethanthreeorfourmainscaffoldlimbs.Selectshootsthathavethewidestangleswheretheyattachtothetrunkandthatarenotallatthesameheight.Peachlimbswithpoorcrotchessplitoutmorefrequentlythanlimbsofmanyotherfruittrees.
Removescaffoldlimbsthatmaycompetewiththethreeorfouroriginallyselected.Dothisinthespringofthesecondyearandagaininthethirdyearifnecessary.Headthescaffoldlimbsinthefirstandseconddormantseasonstocausebranchinguntilthereare6to8secondaryscaffoldbranchesand12 to16 tertiarybranches.
Peachtreesbearonlyonl-year-oldshoots(figure 12,page7).Everyyear,pruneenoughtostimulatenewshootgrowthforthefollowingyear’scrop.Peachtreesbranchreadily,sotheywillhavetoomanyweakshootsunlessyouprunethemproperly.Thinoutshoots,leavingthoseofmoderatevigor.Removeallweakorverystrongshoots.
Prunehardestinthetopandneartheendsofthemajorlimbs.Cuttoplimbsbacktosideshootstostiffenthemandreducetreeheight.Peachtreescropmoreconsistentlyandhavelargerfruitsifthey’reprunedheavily.Commonly,upto50percentofthepreviousseason’sgrowthisremovedeachyear.
Prune and plum Trainpruneandplumtreestotheopencenter
system(figure5,page4)withthreeorfourmainscaffoldlimbs.Pruneverylightlyforthefirst5 years.Headonlythelimbsthatwillbepermanentscaffolds,removescaffoldlimbsthatmaycompetewiththethreeorfouroriginallyselected,anddolittleelse.Weightingorbendinglimbsstimulatesearlyproduction.
Inmaturetrees,thinoutthetopeveryfewyearsandremovedeadlimbsastheyappear.Mostplumsandpruneshaveamplebloomeveryyear,soyouonlyneedtopruneenoughtocontrolheightandspread,keepthetreesfairlyvigorous,andpreventlimbbreakage.
Japanesevarieties(suchasShiro,Redheart,andBurbank)havemanylong,thinshoots,soheadingisfarmoreimportantinthemthanitisinmostEuropeanvarieties.
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Apricot Apricottreesusuallydevelopmanybranches
inthenursery.Selectsomeofthemtobescaffoldbranchesatplantingtime.Cutthesebranchesbackafewinchesandremoveotherbranches.Oneyearafterplanting,cutbacklongshootstoinducebranching.Trainthetreeasyouwouldforpeaches.
Pruningbearingapricottreesismostlyaprocessofthinningoutexcesswoodandheadinglongshoots.Afterasideshoothasproducedfor3or4 years,removeitandletanewshootgrowinitsplace.
FigFigtreescanbegrowninamultipleorsingle-
trunkform.Ifyouliveinaregionwithseverefreezingweather,considergrowingthemultipletrunkformsoyoucanthinouttrunksthatsufferfreezedamage.Inotherregions,asingle-trunkformwiththreetofivescaffoldbranchesissuitable.
Amaturefigtreecanreachthesizeofawalnuttree.Besuretoprunethetopforgoodlightpenetrationintothecanopy.Figsproducefruitonthecurrentseason’sshoots,soheadingbranchestostimulateshootgrowthishelpful.
PersimmonTherearetwotypesofpersimmontrees,
AmericanandAsian.TheAsianpersimmontreeissmallerwhenmaturethantheAmericanandneedslessmaintenancepruningtocontainitsheight.Amultiplescaffoldsystemwiththreetofivemainscaffoldbranchesissuitableforpersimmons.
Pruning an old, neglected fruit treeAtreethathasn’tbeenprunedforseveralyears
hasadensethicketofuprightshootsinthetopandmanyweak,pendulant(downwardfacing)spursystemsfurtherdown(figure17).It’sbesttoprunethetreebackintoshapegraduallyoverseveralyears,ratherthantryingtodothewholejoballatonce.
Afteryouidentifythemainscaffoldbranches,sawoutanyexcesslargebranches.Cutladderbayssoyoucanplaceyourladderinthetree’scenter.Climbashighonyourladderinthetree’scenterasyouintendtopick,andcutthemainscaffoldlimbsdowntotheheightthatyoucanreach.
Removelimbsthatoverlaporhangdownintootherlimbs.Thinoutmostoftheuprightshoots,
leavingsomeofthesmallerones.Cutbackweak,pendulantlimbs.Graduallyinvigoratethespursystemsbycuttingbacksomeandremovingothers.Keepthecenterofthetreefairlyfreeoflimbssothatlightcanpenetrate.
Don’theadshoots.Removethementirely,orletthembearfruitandrelyontheweightofthefruittobringthemdown.Thinoffshootsontheinsideofuprightbranchessothatfruitwillpullthemtotheoutside.
Nut trees
Walnut Cutoffanewlyplantedwalnuttree4or5feet
abovetheground.Ifyoudon’tmakethiscut,thetreewon’tgrowmuchforseveralseasons.Thelowestlimbsofawalnuttreehaveahabitofdrooping,sotheyshouldoriginatefairlyhighonthetrunk.
Figure 17. In a poorly pruned tree, upper limbs shade out lower limbs, and a dense thicket of suckers appears in the top. Cut the drooping terminal portion to a more upright branch (arrows). Remove some of the suckers, cutting close to the limb; thin out side shoots on others so that they’ll bend over with the weight of the fruit.
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Selectthreetofivemainscaffoldbranchesinthefirstandsecondgrowingseasonsandremoveexcessbranchesatthattime.Useamodifiedcentral-leadersystemtohelpformwide-angledscaffoldlimbs.
Afterthescaffoldbrancheshavedeveloped,nofurtherpruningisrequired.Pruningdoesn’thurtwalnuttrees,butthey’resolargethatit’sdifficulttoprunethetop(wherepruningwoulddothemostgood).Pruningwillinvigoratemostold,weakwalnuttrees.
Hazelnut Innature,hazelnutsgrowasbushes,butyoucan
forcethemtogrowinasingletrunkbyannuallyremovingthesproutsthatgrowatgroundlevel.Trainthetreewiththreeorfourscaffolds,similartotrainingpeaches(page10).
Tobemostproductive,ahazelnuttreeshouldmake6to8inchesofnewterminalshootgrowth
everyyearonshootsatshoulderheight.Frequentpruninghelpsmaintainthisgrowth.
Prunehazelnuttreeslikepeaches,butlessseverely.Hazelnutwoodisespeciallysusceptibletowood-rottingfungi,soit’simportanttomakecutsatthebranchcollarwithlimbsortrunk.
Chestnut Pruningmethodsforwalnutsalsoworkfor
chestnuttrees.Headanewlyplantedtreearound4 feetfromtheground,andselectthreetofivescaffoldbranchesafterthefirstseasonofgrowth.Useamodifiedcentral-leadersystemtohelpformwide-angledscaffoldlimbs.Ifscaffoldbrancheshavenotproducedlateralgrowthinthefirst3feet,thenheadthescaffoldtostimulatelateralbranching.
Inmaturetrees,pruneinthetoptoensuregoodlightpenetrationthroughoutthecanopy.Fullymaturechestnuttreesgrowto40feettall.
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PublishedApril1992.RevisedJuly2011 $3.00