Edge Feathering and Crown Modification
- Edge feathering is thinning within the first tree length of the stand
- Where possible, retain the most windfirm trees.
- Dont feather edges in dense stands of slender trees.
- Feathering mimics the pattern of partial damage that develops along
moderate risk boundaries.
- During salvage, leave standing and leaning trees in place if possible.
- Crown modification includes: topping, top-pruning, sailing, spiral
- Removing the top 1/3 of the crown reduces wind loading by 50%.
- Topping and top pruning can reduce tree vigour and cause trees to
produce multiple leaders.
- There are helicopter-based techniques for topping and top pruning.
- Heli-saw productivity ranges from 1244 trees/hour, costing $1968/tree.
It is best suited to mature stands.
- Heli-shear productivity ranges from 937 trees/hour, costing $2391/tree.
It is best suited to 2nd growth stands.
- Manual topping productivity ranges from 1.31.9 trees/hour, costing
- Sailing and spiral pruning are manual arboricultural techniques that
preserve the top of the tree.
- In sailing, windward branches are removed from the lower 2/3 of the
- In spiral pruning, branches are removed throughout the crown.
- Productivity for sailing and spiral pruning treatments is lower than