ISA Arborist Certification Exam Questions and Answers Updated 2026

ISA Arborist Certification Exam
Questions and Answers Updated
2026
OneMwayMtoMdetermineMhowMgoodMtheMdrainageMisMinMaMpotentialMplantingMareaMis
Mto:M

A.MTestMtheMsoilMpHM

B.MUseManMairMexcavationMdeviceMtoMloosenMtheMsoilM

C.MPerformMaMwaterMpercolationMtestM

D.MAnyMofMtheMaboveM-MAnswerMC.MPerformMaMwaterMpercolationMtest



TheMmajorMwater-conductingMcellsMinMangiospermsMareMthe:M

A.MTracheidsM

B.MFibersM

C.MParenchymaMcellsM

D.MVesselsM-MAnswerMD.MVessels



CarbonMsequestrationMoccurs:M

A.MDuringMphotosynthesisM

B.MAsMemissionsMfromMvehiclesMareMreducedM

C.MAsMsunlightMcombinesMwithMairMpollutionM

D.MAsMwoodMdecaysM-MAnswerMA.MDuringMphotosynthesis



ArmillariaMmushroomsMareMoftenManMindicatorMof:M

A.MPoorMsoilMbiologyM

B.MStressedMtreesM

C.MRootMdecayM

D.MAllMofMtheMaboveM-MAnswerMD.MAllMofMtheMabove



AMlandscapeMarchitectMhasMdesignedMaMshadedMnatureMwalkMbehindMaMpreschool.MWhi
chMofMtheMfollowingMwouldMnotMbeMaMgoodMtreeMqualityMinMthisMspace?M

A.MAttractiveMfallMcoloringM

,B.MAbundantMfruitingM

C.MBroad,MdeciduousMcanopyM

D.MAllMofMtheMaboveM-MAnswerMB.MAbundantMfruiting



AMspringMpoleMrefersMto:M

A.MNewMgrowthMonMaMtreeMorMshrubMafterMbudMbreak.M

B.MAMpoleMsawMorMprunerMusedMinMspring,MdesignedMtoMminimizeMdamageMtoMslough
ingMbark.M

C.MAMtreeMtrunkMthatMhasMhadMallMitsMbranchesMremoved.M

D.MAMpinnedMbranchMorMsmallMtreeMunderMtensionMbyMfallenMtrees.M-
MAnswerMD.MAMpinnedMbranchMorMsmallMtreeMunderMtensionMbyMfallenMtrees.



TheMbranchMcollarMisMformed:M

A.MByMtheMannualMprocessMbyMwhichMtissueMisMlayeredMwhereMtheMbranchMandMstem
MmeetM

B.MOnlyMinMthick-barkedMtrees,MwhereMbarkMhasMbuiltMupMaroundMaMunionM

C.MOnlyMwhenMbranchesMdieMwithoutMfalling,McausingMtheMtreeMtoMstartMtoMbuildMaM
collarMalongMtheMdeadMbranchM

D.MAtMtheMinternodes,MdueMtoMtwigMelongationM-
MAnswerMA.MByMtheMannualMprocessMbyMwhichMtissueMisMlayeredMwhereMtheMbranch
MandMstemMmeet



WhenMpruningMaMyoungMtree,MoneMreasonMtoMleaveMtemporaryMbranchesMthatMareMlo
werMthanMtheMlowestMpermanentMbranchMis:M

A.MTheyMhelpMprovideMenergyMtoMtheMtrunk.M

B.MTheyMcontributeMtoMproperMtaperMdevelopment.M

C.MTheyMprovideMshadeMtoMtheMyoungMtrunkMtissue.M

D.MAllMofMtheMaboveM-MAnswerMD.MAllMofMtheMabove



WhichMpruningMsystemMisMstartedMwithMaMseriesMofMheadingMcuts,MfollowedMbyMannua
lMsproutMremoval?M

A.MPollardingM

B.MTopiaryM

C.MNaturalM

, D.MEspalierM-MAnswerMA.MPollarding



AMsignificantMnumberMofMsmall,MfruitingMbodiesMalongMaMbranchMindicates:M

A.MSapwoodMrotM

B.MHeartwoodMrotM

C.MBasalMrotM

D.MWhiteMrotM-MAnswerMA.MSapwoodMrot



WhenMfellingMaMtree,MtheMescapeMpathMshouldMbe:M

A.MAtMaM45-degreeMangle,MawayMfromMtheMdirectionMofMfallM

B.MAtMaM45-degreeMangle,MtowardMtheMdirectionMofMfallM

C.MOppositeMtheMdirectionMofMfallM

D.MTowardMtheMdirectionMofMfallM-MAnswerMA.MAtMaM45-
degreeMangle,MawayMfromMtheMdirectionMofMfall



AllMofMtheMfollowingMareMrecommendationsMforMsupportingMaMhealthyMlandscapeMexcep
t:M

A.MPurchasingMaMdiverseMselectionMofMpest-
resistantMplantMspeciesMB.MSelectingMhealthyMnurseryMstockM

C.MPre-treatingMwithMaMbroad-
spectrumMpesticideMbeforeMmulchingMD.MAllMofMtheMaboveM-MAnswerMC.MPre-
treatingMwithMaMbroad-spectrumMpesticideMbeforeMmulching



TheMcorkMcambiumMcombinedMwithMtheMexternalMlayerMofMbarkMareMcollectivelyMcalled
Mthe:M

A.MPeridermM

B.MParadoxM

C.MCambidermM

D.MCambiumM-MAnswerMA.MPeriderm



AllMofMtheMfollowingMareMdeciduousMconifersMexcept:M

A.MBaldMcypressM(TaxodiumMdistichum)M

B.MTamarachM(LarixMlaricina)M