Certified Arborist Test Tree Pruning Principles 3

Question 1

What pruning objective is most appropriate for young trees in the establishment phase?

Accepted Answer

Structural pruning to establish sound architecture through early corrective training cuts

Answer

Aesthetic shaping to achieve the desired mature form immediately after planting

Answer

Heavy crown reduction to balance the crown-to-root ratio after transplanting

Answer

Removal of all competing laterals to maximize apical dominance and height growth

Question 2

What is included bark, why is it a structural defect, and what pruning action is typically recommended?

Accepted Answer

Bark folded into the inside of a narrow-angle branch union that prevents proper wood formation, creating a weak point prone to splitting

Answer

Bark callus growth over a wound that indicates the tree's woundwood production is compromised

Answer

Bark inside a cavity that indicates decay has reached the inner bark layer of the parent stem

Answer

Loose, dead bark on a branch that should be removed during routine pruning inspections

Question 3

What does ANSI A300 Part 1 specify regarding the maximum amount of live crown that can be removed in a single pruning operation?

Accepted Answer

No more than 25% of the live crown should be removed in any single pruning operation, with less for stressed trees

Answer

Up to 50% of the live crown may be removed from any tree regardless of health status

Answer

Exactly one-third of the live crown is the standard maximum for all species and conditions

Answer

There is no specific maximum — the decision is left entirely to the judgment of the certified arborist

Question 4

What is the difference between a thinning cut and a heading cut in pruning, and which is generally preferred for most mature tree pruning objectives?

Accepted Answer

Thinning cuts remove branches back to their origin or to a lateral; heading cuts shorten branches to a bud or lateral — thinning cuts are preferred for most mature tree objectives

Answer

Thinning cuts remove entire branches back to their origin; heading cuts remove branch terminals back to laterals — heading cuts are preferred for shaping

Answer

Heading cuts remove the entire branch at its origin; thinning cuts shorten branches — thinning is preferred for formal hedges only

Answer

There is no practical difference between the two cuts — the terms are interchangeable in modern arboriculture

Question 5

What is 'lion's tailing' and why is it considered poor arboricultural practice?

Accepted Answer

Stripping interior and lower branches from limbs while leaving foliage only at branch tips

Answer

Removing all branches from the lower half of a tree's crown to create high clearance

Answer

Removing dead wood from branches in a way that causes branch tip dieback to spread

Answer

Reducing the crown to a single dominant leader by removing all lateral scaffold branches

Question 6

Which pruning method involves cutting back branches to lateral branches approximately equal to one-third or more the size of the removed branch to reduce overall tree height or spread?

Accepted Answer

Crown reduction — making drop-crotch cuts to reduce height while maintaining natural structure

Answer

Crown thinning — removing entire branches throughout the crown to reduce density uniformly

Answer

Crown cleaning — removing dead, dying, diseased, or crossing branches from the crown

Answer

Crown lifting — removing lower branches to increase the clearance beneath the crown