Pruning and tree supporting system

PruningTree Supporting System

Pruning

Proper pruning can lengthen the life span and maximize the greening effect of trees. However, improper pruning can damage the tree and cause potential tree failure in the future. Moreover, pruning should be conducted by qualified and certified tree workers to ensure the quality and safety.

Type of Pruning

Crown Cleaning Removal of dead, crossed and hanging branches	Crown Thinning Selective pruning of the crown to reduce density
Crown Reduction Reducing of the crown size	Crown Raising Selective pruning of the lower branches
Restoration Pruning Pruning to improve/restore the damaged tree form

Incorrect Pruning & Impact

Incorrect Pruning	Impact
Topping Topping-1 Topping-2	The natural tree form will be destroyed. Pruning at wrong location facilitates decay and leads to potential hazard. Large reduction of crown size reduce the capacity of photosynthesis greatly and excessive growth of epicormic shoot may be resulted.
Lion’s Tailing Lion’s Tailing	The natural tree form is destroyed and the risk of tree failure increased.
Over-pruning (prune over 25% within one growth season) Over-pruning	Large reduction of crown size reduce the capacity of photosynthesis greatly and excessive growth of epicormic shoot may be resulted.
Improper wound dressing Improper wound dressing-1 Improper wound dressing-2	Wound dressing cannot protect the wound and may disturb the formation of wound wood.
Leaving unnecessary stubs Leaving unnecessary stubs	The remaining stub may easily decay and induce pest growth and disease.
Bark tearing Bark tearing	Create a large wound may induce pest growth and disease.
Flush Cut Flush Cut	The ability of wound wood formation will be weakened
Large pruning wound Large pruning wound	Large wound is difficult to heal and may induce pest growth and disease.
Jagged wound Jagged wound	Jagged wounds heal badly and facilitate decay.

Correct Pruning & Purposes

Correct Pruning	Purpose
Pruning only when necessary	Unnecessary pruning should be avoided as pruning creates wound unavoidably.
Cut outside the branch collar	Damaging the branch collar may badly affect the wound wood formation.
Use “3-Point Cut”	Avoid bark tearing
Clean cut	Clean cut can facilitate wound healing.
Do not prune over 25% within one growth season.	To ensure the tree have sufficient foliage for healthy growth

For more details, please visit:
Do’s and don’ts in pruning 　　 Pruning tips

Tree Supporting System

Newly planted trees and defective trees have higher risk of tree collapse. Cabling and propping are the most common methods for tree supporting. Certified Arborist should be consulted before installing any supporting system.

Tree Supporting is Required

Severe leaning Severe leaning-1 Severe leaning-2	Rootplate dislodgement Rootplate dislodgement-1 Rootplate dislodgement-2
Newly planted tree Newly planted tree	Tree with structural defect. e.g. Co-dominant trunks, included bark, crack, cavity, etc. Tree with structural defect-1 Tree with structural defect-2

Improper Tree Support & Impact

Improper Tree Support	Impact
Leaving the tree support for too long Leaving the tree support for too long-1 Leaving the tree support for too long-2	For the newly planted trees, the supporting system should be adjusted or removed after one year.
Cable is too tight Too tight-1 Too tight-2	Tree may be strangled by the tight cable.
Direct contact with tree Direct contact with tree-1 Direct contact with tree-2	Tree with direct contact of the cable/prop may be damaged.
Excessive tree support Excessive tree support	Obstruct tree growth
Lack of regular adjustment and checking for supporting system	Regular adjustment of cable is needed to fit the tree growth. Inspection is also needed to ensure that the tree supporting system is in good condition.