ISA Pruning & Tree Maintenance 2

Question 1

What is crown cleaning and what types of branches are targeted?

Accepted Answer

Selective removal of dead, dying, diseased, crowded, weakly attached, and broken branches from the crown

Answer

Crown cleaning is the selective removal of dead, dying, diseased, broken, and weakly attached branches from the tree's crown. It is the most basic and commonly performed pruning operation.

Question 2

What is the appropriate maintenance schedule for inspecting and adjusting supplemental support systems (cables and braces) installed in trees?

Accepted Answer

At least annually, and after every major storm event

Answer

Supplemental support systems require annual inspection to check hardware condition, cable tension, tree growth around hardware, and any new defects. Additional inspections should follow any major storm event.

Question 3

When raising the crown of a mature tree for clearance, what guideline helps maintain tree health and structural stability?

Accepted Answer

Remove no more than one-third of the live crown height, and maintain at least two-thirds of the total tree height in live crown

Answer

To maintain tree health and structural stability, crown raising should preserve at least two-thirds of the total tree height in live crown. Removing too many lower branches reduces photosynthetic capacity and can create a top-heavy crown.

Question 4

What is the purpose of crown thinning and how does it differ from lion-tailing?

Accepted Answer

Crown thinning selectively removes branches throughout the crown to reduce density while maintaining even distribution; lion-tailing removes only interior branches, leaving tufts at branch ends

Answer

Crown thinning removes select branches evenly throughout the crown to reduce density while maintaining the tree's shape and balanced branch distribution. Lion-tailing strips interior foliage, concentrating weight and wind load at branch tips — a harmful practice.

Question 5

At what stage of development is structural pruning most effective and why?

Accepted Answer

During the young, actively growing stage when developing branches are small and the tree can quickly close pruning wounds

Answer

Structural pruning is most effective on young trees because defects are corrected while branches are small (wounds close quickly), the tree's natural form can be directed, and the energy cost of pruning is minimal relative to the tree's growth capacity.

(ISA) ISA Certified Arborist Practice Test

(ISA) ISA Certified Arborist Practice Test

ISA Pruning & Tree Maintenance 2