The Tree Care Industry Association (TCIA) is urging climbers not to use climbing spikes when pruning trees.
Spikes are traumatizing to living trees and create unnecessary damage.
Each puncture from a climbing spike produces a certain amount of tree tissue death around it to some extent, varying from tree to tree. In most cases, isolated wounds will seal, but over time, groupings of spike holes can cause the entire area on the trunk to die back with no chance of recovery.
The likelihood of piercing the cambium (living tissue beneath the bark) is high, even with larger trees and thick bark. If soon after the work is performed with spikes there is sap oozing from the wounds, the tree is responding to spike damage. Repeated damage of this type is harmful to the tree.
The use of tree climbing spikes (spurs, hooks, gaff, irons, etc.) is a once-practiced method of climbing trees that has proven to be harmful to long-term tree health.
There are certain exceptions, when spikes are allowed, such as:
When the tree is being removed.
When branches are more than throwline distance apart and there is no other means of climbing the tree (for example: when there are no branches lower than 50 feet), with no access for an aerial lift device or crane.
If the tree is too close to power lines and cannot be accessed safely by other means.
To reach an injured climber.