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.Respiration 2.Foliage – Fine Roots 3.{Reproduction} 4.Primary Growth 5.Secondary Growth – Secondary Compounds

Lag in Response Not enough excess photosynthate to add foliage