What are forest products?
Forest products are things people take from forests. Timber is wood used to build and make things. Non-timber products include mushrooms, honey, bamboo, resin and fruits.
Wood is useful because it is strong for its weight, easy to cut and it grows again. A forest used with care keeps giving.
From log to board: sawing
A log is a trunk cut to a fixed length. A saw cuts it into boards (thin flat pieces) and beams (thick pieces).
Each cut turns some wood into sawdust. A thin saw blade wastes less. Number of boards is about log width ÷ board thickness.
Drying wood (seasoning)
Fresh wood is full of water. If you use it wet, it bends, cracks and shrinks later. So we dry it.
- Stack boards with small sticks between them. Air must flow.
- Keep the stack off the ground and out of rain.
- Dry until the wood has about 12 to 15% water for indoor use.
Charcoal and mushroom logs
Charcoal: heat wood in a closed kiln with very little air. Water and gases leave, and black carbon stays. It is light, burns hot and gives little smoke.
Mushroom logs: cut a log from a broadleaf tree, drill small holes, push in mushroom seed (called spawn), and keep the log shaded and damp. In a few months mushrooms grow out. The mushroom is a fungus and eats the dead wood.
Try it
In the 3D: in the last step, guess how many boards a 40 cm log gives with 5 cm cuts. Then move the sliders and check.
At home: weigh a wet wooden stick. Leave it in a dry shaded place for a week. Weigh it again. The weight lost is water.
Key formulas and definitions
- Number of boards ≈ log width ÷ board thickness
- Water content (%) = (water weight ÷ dry wood weight) × 100
- Charcoal yield ≈ 20% of wood weight
- Key terms: timber, seasoning, kiln, spawn, sawdust
Worked examples
1. A log is 40 cm wide. Each board is 5 cm thick. How many boards?
40 ÷ 5 = 8 boards (a little less in real life because of sawdust).
2. 50 kg of wood is made into charcoal. About how much charcoal do we get?
20% of 50 kg = 10 kg.
3. A wet board weighs 160 g. After drying it weighs 100 g. How much water did it lose?
160 − 100 = 60 g of water. Water lost is 60 ÷ 160 = 37.5% of the wet weight.
Common mistakes
- Using wet wood for furniture. It will bend and crack as it dries.
- Stacking boards flat on top of each other with no gap. Air cannot pass and the wood can rot.
- Thinking charcoal is just burnt wood. It is made with very little air so it does not burn away.
- Thinking mushrooms are plants. They are fungi.