Tree Architecture and Growth

Part 1

Apical Growth

• Apical meristem = bud– Primary growth

• Preformed

• Indeterminant or sustained

Crown Form

• Excurrent

• Decurrent

Mechanisms

• Branch angle

• Geotropism

• Weight (gravity)

Epinasty

• Epinastic control

– angle and length of side branches

– genetics and environment

Shade

• Side shade– Trees do not lose form

• Shade from above– high shade – low shade– becomes more diffuse– trees can lose epinastic control

Cross section

Shade

• Side shade– Trees do not lose form

• Shade from above– high shade – low shade– becomes more diffuse– trees can lose epinastic control

Multilayer vs. Monolayer

Multilayer

Monolayer

Release

• Interaction of:

– the environment (old new)

– the silvical characteristics of the tree

– tree condition

Tree Attributes

• Amount of foliage

• Amount of aphotosynthetic area

• Sun leaves– Shade leaves

• Epinastic control

Priorities for Photosynthate

1. Respiration2. Foliage – Fine Roots3. {Reproduction}4. Primary Growth5. Secondary Growth –

Secondary Compounds

Lag in Response

• Not enough excess photosynthate to add foliage