Tree structure

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Tree structure

• By Edward F. Gilman
• Department of Environmental Horticulture
• University of Florida
• http//hort.ufl.edu/woody/planting

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Tree Structure

• Whats the Problem?

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What is good structure?
Outline of topics

• Forest grown vs. open grown tree
• Codominant stems
• Good branch attachment
• Structurally sound tree

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Forest grown tree
vs..
Open grown tree

• How do they develop on their own?

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Trees in the forest grow with one trunk, and
codominant stems toward the top of the tree
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Codominant stems form far up into the canopy on
most forest trees
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Open grown trees

• Canopy develops low on the trunk
• Canopy spreads wide
• Tree is often wider than tall

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Its party time for all
Its all about access to sunlight
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(No Transcript)
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Appears to be a nice tree
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Close-up of base of tree
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Huge crack
Same tree five years later
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Fall down go boom tree
Keep an eye on this side of the tree
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I thought I heard something creak last night
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What is good structure?
Outline of topics

• Forest grown vs. open grown tree
• Codominant stems
• Good branch attachment
• Structurally sound tree

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2. Codominant stems
Stems nearly same diameter
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These are weak
Elephant ears
Severely acute angle
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Why are they a problem?
Included barkbeginning to form
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Bark inclusion
Decay and discoloration from self wounding
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Bark inclusion
Closed crack indicating inclusion
Near-normal wood formation
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Closure crack indicating inclusion
Bark inclusion
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Bark inclusion (Not a codominant stem!)
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Close-up of closure crack
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What is good structure?
Outline of topics

• Forest grown vs. open grown tree
• Codominant stems
• Good branch attachment
• Structurally sound tree

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3. Good branch attachment

• How does a BRANCH form?
• What are the indicators?

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(No Transcript)
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Branch bark ridge present

• Some branch unions have a prominent branch bark
  ridge

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No branch bark ridge
Collar
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Pine union

• Collar is visible as a swelling at the base of
  the branch
• Branch bark ridge (arrows) is visible as a dark,
  rough bark region on the top and sides of the
  union

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Wood orientation at union

• Peel the bark from the union
• Note how trunk wood grows out onto the base of
  the branch (dotted line is edge of trunk wood)

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Desirable branch size
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(No Transcript)
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Strong union
Weak union
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What is good structure?
Outline of topics

• Forest grown vs. open grown tree
• Codominant stems
• Good branch attachment
• Structurally sound tree

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4. Structurally sound tree

• Scaffold branches spaced vertically.
• Rule of thumb about 5 of trees ultimate
  height.
• Scaffold branches spaced radially none directly
  above another.
• Consistently maintain 60 L.C.R.

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Good structure
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Stems too close together
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Pruning
Is a solution that will be discussed in another
presentation.
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Tree structure

• By Edward F. Gilman
• Department of Environmental Horticulture
• University of Florida
• http//hort.ufl.edu/woody/planting