12 Wood

Identify the features that distinguish primary from secondary growth, and explain how the latter is required to produce wood (and be able to define wood)

• Primary Growth

  • Contributed to unidirectional stem elongation

  • Occurs at  Apical meristems

• Secondary Growth

  • Contributed to stem widening and wood development

  • Lateral meristems

Draw a cross section of a tree, and label where secondary xylem, vascular and cork cambia, bark and phloem are found.

Explain the difference between hardwood and softwood in terms of the kinds of trees that produce each, and what xylem cell types can be found in each

• Soft wood: gymnospersms (tracheids)

  • Pine, spruce, larch, cypress

• Hardwood: angiosperms (tracheids and vessels)

  • Oak, maple, chestnut, walnut

Discuss major and minor uses of wood

• Primarily:

  • Fuel: firewood, coal

  • Paper

  • Lumber