Timber Grows on Trees!

1. Timber Grows on Trees! • Stores carbon • Sustainable • Planting to meet demand • Recyclable • Selection of product • Species of Timber • Type of Processing • Seasoning • Treatment Radiata pine plantation Photo: PTAA Photo: Geoff Boughton

2. Hardwoods broad leaf generally higher densities often dark in colour Softwoods needle-like leaves generally lower densities often light in colour Hardwoods and Softwoods Photo: Geoff Boughton Photo: Geoff Boughton Native Australian h’wds include mountain ash brown box spotted gum jarrah common Australian s’wds include radiata pine cypress pine hoop pine

3. Tree Growth • New wood on outside of tree • oldest wood on inside of tree • youngest wood on outside • diameter largest at base • one ring (layer) per year • Tree in forest grows towardslight • trunk straight • lower branches die • leaving small knots in wood • Bark protects wood from damage • tree sheds bark each year

4. Production of Wood • Sapling - fibrous juvenile wood • becomes pith

5. Production of Wood • Pith - the start of growth in the tree • the original sapling • Cambium - growth cells • wood cells created on inside • bark cells created on outside • Bark - protects wood • new bark made continually • bark falls off each year • Wood - • new wood cells on outside • newest wood takes nutrients to leaves

6. Production of Wood • Pith - the start of growth in the tree • the original sapling • Cambium - growth cells • wood cells created on inside • bark cells created on outside • Sapwood - newest wood • on outside of tree (~ 1-3 cm) • takes nutrients from root to leaves • Heartwood - older wood • cells closed - can’t pass nutrients • storage for waste - extractives

7. Production of Wood • Pith - the start of growth in the tree • the original sapling • Cambium - growth cells • wood cells created on inside • bark cells created on outside • Sapwood - newest wood • new wood has thin cell walls • sapwood most effective on outside • Heartwood - older wood • oldest sapwood becomes clogged • new heartwood added on outside

8. Growth Rings • Early wood • rapid growth at beginning of growing season • thin, large cells - lighter colour Photos: Geoff Boughton • Late wood • slower growth, often limited by lack of water • thick small cells - darker colour • gives the growth ring Photos: Geoff Boughton

9. Growth Rings • Generally one ring per year • some climates may have more than one growth season per year • fires or disease may produce an extra ring • Growth rings give texture and figure to wood Photos: Geoff Boughton