HomeMy WebLinkAboutTR_ISA_Tree_Risk_Assessment_FormISA Basic Tree Risk Assessment Form
Client ______________________________ Date _________ Time _______ _
Address/Tree location ___________________________ Tree no. ______ Sheet of
Tree species ____________________ dbh ______ Height _____ Crown spread dia. _____ _
Assessor(s) Time frame Tools used _____________ _
Target Assessment
Target zone
Occupancy r,. • ~ ,:: :E ,:: .... .... ., £ Q.) :E rate 0 ., ,:: ., .0 .., X .of: :E ..... QJ) O""· ~E 1-rare -~ j: ,§ g:, ... (1J (1J -~.; {2.:, Target description ~ ,:: ~ X 2 -occasional u ..... uu ,:: ... Q. ~£ QJ "' 3-frequent -~ ., ·~:p
~:§ u > ... u ~,....i (1J 0 "' (1J -~ 4-constant ti:.E ., ~ {2. {2. 0:: Q.
1
2
3
4
Site Factors
History of failures __________________________ _ Topography FlatD SlopeD ____ % Aspect __
Site changes None D Grade change D Site clearing D Changed soil hydrology D Root cuts D Describe ________________ _
Soil conditions Limited volume D Saturated D Shallow D Compacted D Pavement over roots D ___ % Describe ___________ _
Prevailing wind direction ___ Common weather St rong winds D Ice D Snow D Heavy rain D Describe _____________ _
Tree Health and Species Profile
Vigor Low D Normal D High D Foliage None (seasonal) D None (dead) D Normal % Chlorotic % Necrotic %
Pests________________________ Abiotic ________________________ _
Species failure profile Branches D Trunk D Roots D Describe ______________________________ _
Load Factors
Wind exposure Protected D Partial D Full D Wind funneling D ___________ Relative crown size Small D Medium D Large D
Crown density Sparse D Norma l D Dense D Interior branches Few D Normal D Dense D Vines/Mistletoe/Moss D ________ _
Recent or planned change in load factors---------------------------------------
Tree Defects and Conditions Affecting the Likelihood of Failure
-Crown and Branches -
Unbalanced crown D LCR ___ %
Dead twigs/branches D __ % overall Max. dia.
Broken/Hangers Number____ Max. dia.
Over-extended branches D
Pruning history
Crown cleaned D
Reduced D
Flush cuts D
Thinned D
Topped D
Raised D
Lion-tailed D Other _________ _
Cracks D _______________ Lightning damage D
Codominant D _______________ Included bark D
Weak attachments D ________ Cavity/Nest hole __ % circ.
Previous branch failures O ______ Similar branches present 0
Dead/Missing bark D Cankers/Galls/Burls O Sapwood damage/decay D
Conks O Heartwood decay O _________ _
Response growth---------------------
Main concern(s) --------------------------------------------
Load on defect N/A D Minor O Moderate O Significant O ___________________ _
Likelihood of failure Improbable O Possible O Probable O Imminent O --------------------
-Trunk-
Dead/Missing bark O Abnormal bark texture/color 0
Codominant stems D Included bark D Cracks D
Sapwood damage/decay D Cankers/Galls/BurlsD Sap ooze 0
Lightning damage D Heartwood decay O Conks/Mushrooms 0
Cavity/Nest hole __ % circ. Depth ___ Poor taper 0
Lean __ ° Corrected? _____________ _
Response growth ________________ _
Main concern(s) ________________ _
Load on defect N/A O Minor O Moderate D Significant D
Likelihood of failure
Improbable O Possible D Probable 0 Imminent D
-Roots and Root Collar -
Collar buried/Not visible D Depth___ Stem girdling D
Dead O Decay O Conks/Mushrooms 0
Ooze O Cavity D __ % circ.
Cracks O Cut/Damaged roots O Distance from trunk __ _
Root plate lifting 0 Soil weakness D
Response growth _______________ _
Main concern(s) -----------------
Load on defect N/A D Minor O Moderate D Significant 0
Likelihood of failure
lmprobableD Possible 0 Probable 0 lmminentO
Page I of 2
Daniel J Maple BL23-5-years
1 2
S/SW x x TLPS
Risk Categorization
... QJ ,._ .c E QJ
QJ ..c ::::i u E C: C: ::I QJ C: QJ ro C: :;; 0 .... :e N .!!! "' 'iii .... ..c " Conditions "'C QJ Target 0
C: .... -tll) a. ,._ ro ,._
0 Tree part of concern ro {2 protection .5 I.) Q. LL.
1
2
3
4
Matrix I. Likelihood matrix.
Likelihood Likelihood of Impacting Target
of Failure Very low Low Medium High
Imminent Unlikely Somewhat likely Likely Very likely
Probable Unlikely Unlikely Somewhat likely Likely
Possible Unlikely Unlikely Unlikely Somewhat likely
Improbable Unlikely Unlikely Unlikely Unlikely
Matrix 2. Risk rating mat rix.
Likelihood of Consequences of Failure
Failure & Impact Negligible Minor Significant Severe
Very likely Low Moderate High Extreme
Likely Low Moderate High High
Somewhat likely Low Low Moderate Moderate
Unlikely Low Low Low Low
Notes, explanations, descriptions ______________ _
Mitigation options
Overall tree risk rating
Overall residual risk
Low O Moderate O High O Extreme 0
Low O Moderate O High O Extreme 0
Failure
QJ QJ
:;; j:j
"' -~ ..Q e 0 c.. c..
Likelihood
Consequences Failure & Impact Impact (from Matrix 1) Risk ... ... > QJ C: rating "' ,:
== E > .c: a:; :;; "' QJ ..S! a:; == ~ :§ u of part ,: .:! QJ > ... u:: ~ ·e > "O .c: ::!: E a:; i:'.' 00 0 ·c (IJ (from ~ == QJ OJ) i: ,: > .5 0 ~ :i: 0 -"' ~ QJ ~ -~ QJ _, :::, "' ::; z "' "' Matrix2)
1 t .. t
L T + T
1 l I
r 1 I I + + I l + -I
l -T +
'
1 1 f 1 r r
r
.,. r l I
1 t-
l +-+ + t
_._
l 1-l
I t T i I
Nonh
j
/-~.
( ;·
~
Residual risk
Residual risk
Residual risk
Residual risk
Work priority 1 0 2 0 3 0 4 0
Recommended inspection interval ________ _
Data O Final O Preliminary Advanced assessment needed ONo DYes-Type/Reason ______________________ _
Inspection limitations ONone OVisibility DAccess OVines DRoot collar buried Describe ___________________ _
1his datasheet was produced by the International Society of Arboriculture (ISA) -2013 Page 2 of 2