THE WORLD OF TREES
by Margaret Guzman Wainwright
1. The trunk is divided into
1.1. wood
1.1.1. a new layer each year
1.2. cambium layer
1.2.1. where the tree growth takes place
1.3. bark
1.3.1. the outer part, keeps the wood from drying out
1.3.2. Protects the tree from parasitic animals or plants
1.3.3. Protects the tree from invasion of desease
1.4. inner bark
1.5. contain pipelines that carry food from the leaves to the roots
2. A tree grows from a seed
2.1. the seed grows into a young plant called sapling
2.2. The stem grows lengthwise at its tip, where a small bud produces new growth
3. Important trees
3.1. California redwoods
3.1.1. the tallest living trees
3.2. bristlecone pines
3.2.1. the oldest living things on earth
4. A tree is a tall plant with a single woody stem
4.1. The largest of all living things
4.2. It is called a perennial
5. Dendrologists: scientists who study trees
6. Unusual trees
6.1. banyan
6.1.1. spreads outward by sending thick roots down from its branches to the ground
6.2. candlenut tree
6.2.1. has nuts containing oil that burns very well
6.3. baobab tree
6.3.1. it has a huge trunk that stores water throughout the dry season