Certified Arborist Test Tree Risk Assessment 3

Question 1

What is 'dynamic loading' and why is it more relevant to tree structural failure than static loading?

Accepted Answer

Dynamic loading involves fluctuating forces (wind gusts, impact) that generate higher peak stresses than the average static weight of the tree

Answer

Dynamic loading refers to root growth pressure against soil; static loading is the weight of the tree itself

Answer

Dynamic loading is the weight of ice accumulation on branches; static loading is the weight of the tree structure alone

Answer

Dynamic loading refers to changes in tree weight during the growing season; static loading is winter weight

Question 2

What is the 'two-year rule' (or 'two-week rule') commonly referenced in arboricultural risk management?

Accepted Answer

A recommendation to complete corrective action on high-risk trees within 2 weeks of assessment completion

Answer

Dead wood should be removed within 2 years of discovery before it becomes a hazard

Answer

The principle that trees should be reassessed every 2 years regardless of condition changes

Answer

Dead branches become hazardous after 2 years because decay weakens branch attachment

Question 3

What condition is indicated by 'basal flare wetwood' or 'slime flux' seeping from a wound or crack at the base of a tree?

Accepted Answer

Bacterial wetwood infection causing internal pressure that forces foul-smelling, discolored sap through cracks or wounds

Answer

Root decay from Armillaria or Phytophthora causing the tree to exude resin through cracks

Answer

Excessive root pressure in spring forcing water-saturated sap through weak points in the bark

Answer

Canker disease causing the cambium to liquefy and exude from infected tissue

Question 4

What does the presence of conks (bracket fungi) or mushrooms at the base of a tree indicate, and how does species identification affect the risk assessment?

Accepted Answer

Conks indicate active wood decay by the fruiting body's parent fungus, and species identification reveals decay pattern, rate, and extent of likely structural compromise

Answer

Conks at the base indicate only surface bark decomposition with no structural significance

Answer

Any fungal fruiting body at the base requires immediate tree removal regardless of species

Answer

Conks indicate past decay that has already been compartmentalized and is no longer progressing

Question 5

What is a 'no-go condition' in arboricultural operations, and provide an example of when a certified arborist must decline to perform tree work?

Accepted Answer

A site or tree condition where proceeding with work creates unacceptable risk to workers or the public, requiring refusal or delay until conditions change

Answer

A condition where tree work is simply not recommended — arborists may still proceed if the client insists

Answer

A regulatory term requiring municipal permits before any tree work can proceed

Answer

A health condition in the tree indicating that pruning would cause more harm than benefit to the tree's survival

Question 6

What is the purpose of a tree risk assessment report, and what minimum elements should it contain according to ISA standards?

Accepted Answer

A formal document communicating risk findings to the tree owner — should include tree description, defects found, failure mode, risk rating, recommended actions, and reassessment interval

Answer

A marketing document summarizing services performed — should include tree species, work performed, and invoice total

Answer

A legal document filed with the municipality whenever a high-risk tree is identified on private property

Answer

A record of pesticide applications required by EPA regulations whenever chemicals are used during the assessment