Post on 09-Jun-2015
Colorado Master Gardener Training
Pruning Cuts
The Art of Pruning
Size and shape control
The Science
of Pruning
Why: Structure & Plant health
How: Natural target pruning
The Art of PruningPruning to Control Shape
The Art of PruningPruning to Control Shape
Branch grows in direction of bud.
The Science of Pruning: Prune with purpose in mind.
How plants respond to woundsNatural Target PruningTypes of pruning cuts
Pruning standards Deciduous trees
New plantingTraining young treesMature treesSpecial need
EvergreensShrubs
Tree physiology
A tree is a series of boxes or “compartments” framed by annual growth rings and rays.
Each “compartment” is filled with tubes (xylem tissue) that transmit water and nutrients up into the tree.
Trees don’t heal, they seal.
Trees don’t heal, they seal.
CODITCompartmentalizatio
n of Decay In Trees
Reaction ZoneChemical change in
cells seal-off or “compartmentalize” the area
Trees don’t heal, they seal.
CODITCompartmentalizatio
n of Decay In Trees
Reaction ZoneChemical change in
cells seal-off or “compartmentalize” the area
CODIT on old Cottonwood trunk
Reaction Zone(Reaction Wood)
CODITCompartmentalization Of Decay In Trees
Reaction Zone
Microorganism Area
Decayed wood
Branch Collar
Branch Bark Ridge
Branch Defense ZoneA ring of cells responsible for Woundwood growth and active in the reaction wood process.
Woundwood closing over pruning cut
Branch collar
Branch defense zone cells
For the Branch Defense Zone to be active, the side branch must be less than 1/2 the diameter of the trunk/parent branch.
Less than 1/3 is preferred.
Natural Target PruningProtects the Branch Defense Zone.
branch bark ridge
branch collar
branch collar
final cut
Terms
CODIT
Reaction Zone
Branch Collar
Branch Defense Zone
Type of pruning cut impacts Ability to defend against decay Regrowth
Natural target pruning cutsRemove side branch back to
larger parent branch/trunk.
Reduction cutsRemove larger branch back to
smaller side branch.
Heading cutsRemove branch tip
1. Preserves the branch defense zone
2. Thins branching pattern Increases sunlight penetration
into plant’s interior
Increases air circulation
3. Only minor influence on height
Natural target pruning cuts remove a smaller side branch back to trunk/parent branch.
Natural Target PruningProtects the Branch Defense Zone.
branch bark ridge
branch collar
branch collar
final cut
Natural target pruning cuts: Use caution to not nick or injure the branch bark ridge.
With proper cut, Woundwood grows over pruning wound
Pruning cut nicked branch bark ridge on bottom. Note how woundwood fails to grow in this area.
Ash Aspen
Natural Target Pruning on Conifers
branch bark ridge
branch collar
final cut
branch collar
Quality of pruning cut?
Reduction cuts remove a larger branch back to a smaller side branch.
NO branch defense zone
Thins branching pattern
Lowers height
Final Cut
Reduction cuts: Angle of final cut splits difference between angle of branch bark ridge and angle perpendicular to branch being removed.
Angle perpendicular to branch being removed
Angle of FINAL CUT
Angle of branch bark ridge
Branch bark ridge
Reduction cuts: To prevent suckering, the smaller branch should be at least 1/3 the diameter of larger branch removed. (At least 1/2 the diameter is preferred.)
Final Cut
Heading cuts make the branch bushier.
Removes the hormone auxinin shoot’s growing tip.
Releases lateral sidebuds
to grow.
Branching at point of pruning gives a bushier plant.
Decreases sunlight intoplant’s interior.
Natural Target Pruning (thinning) Cut
Reduction Cut
Heading Cut
3 cut method for any limb larger than 1”
1. Undercut limb, 12-15” out from crotch.
2. Moving out a couple of inches from 1st, make second cut from top removing limb.
3. Make final cut with Natural Target Pruning techniques.
3 cut method for any limb larger than 1”
Dead limb removal