Properties of wood

• Handout guided notes
• Ask the question, is all wood the same? Why do we use different types of wood?
• Show different types of wood

Conifers, Deciduous, Outer bark, Inner bark, Cambium layer, Sapwood, Heartwood, Hardwood, Softwood, Face grain, Edge grain, End grain

• Types of trees
  • Coniferous- Trees that have needles and cones (Pine Trees). They grow faster then hardwoods. Most wood used is softwood. Most of the wood is used in the construction industry.
    • Show example of a conifer
  • Deciduous- Trees that have leaves and fruits (Walnut Tree). They loose there leaves in the fall. They are hardwoods, and take a long time to grow. That’s why some wood costs a lot of money.
    • Show example of a deciduous tree
• Hardwoods and Softwoods
  • Coniferous are softwoods and deciduous woods are hardwoods
  • Hardwoods are more dense and are harder then softwoods
  • Why would it be important to have a wood that is really hard?
• Parts of a tree
  • Show tree diagram image
  • Outer bark- Outer most part of the tree. It is the trees protection from things. It protects the tree from: extreme heat, cold, insects, and water damage. The tree is always making new bark. Never peel the bark from a tree because it can kill the tree.
  • Inner bark – Carries the food produced from the leaves.
  • The cambium layer- This is the part of the tree that is growing, It is a very small layer, on some trees you can see this layer if you cut into them.
  • Sapwood- Carries the water from the roots to the leaves. It is the newest wood. It has a different color compared to the heartwood.As the cells get old they turn into heartwood. Show log example.
  • Heartwood- The support for the tree, It is what holds the tree up. The wood is dead but it does not decay inside the tree. It is as strong as steel. The cells of the trees are held together with lignin, which is a chemical glue. Heartwood is what most people buy to make furniture, it has the best looks.
• The life of a tree
  • Trees grow the best in the spring
  • They get a lot of sunlight and plenty of water
  • Trees go dormant in the winter
  • They grow slow in the summer because there is not a lot of water
  • In the fall the growth slows down because they are getting ready for winter.
  • Show a diagram on the whiteboard oh how the rings look.
  • The slow growth rings are dark and fast growing rings are light
  • Count the dark rings to find the trees age.
  • Why do people pay more for “Old Growth” trees?
  • The rings are closer together
  • Better looks
  • Modern tree farms the trees grow really fast so the rings are spread out.
  • Show log example with visible rings.
  • How trees are use
  • Show video of lumber cutting
  • The bark is used to burn
  • Parts of the tree that is not suited for lumber is chopped up and used for paper products.
  • Large knot free sections are used for lumber. If there are some knots then it can still be used for lumber it is just a lower grade.
  • The core of the tree is used for veneer, A large knife peels (Think of the shavings from the plane)1/8” thick pieces of wood. It can be made into plywood or sold for furniture if it is a rare wood.
• Lumber surfaces
  • Face grain
  • End grain
  • Edge grain
• Show the straw example to show how wood is fibers.
• Show image to show how you need to cut according to the direction of the grain. If you do not with tools like the plane then the blade will catch.

Review main parts of the tree and what they do.

Hardwoods Vs. Softwoods