TREE
GROWTH RATE
any
time
We have here a variety of trees of known age, mostly planted in 1984, that can be measured--height, diameter breast high, canopy width--any way you like, in feet, inches, or meters. This presents a problem-solving opportunity when the tree is taller than you can reach with your meter stick. Once you have a number, you can calculate growth rate (meters per year). You can add your numbers to the graphs I have for many of the trees.
Some ways to measure a tree too tall to reach the top:
1. Mark a long pole into meters and use it. A 6-meter pole can still do the job, used creatively.
2. One person stands at the bottom of the tree and indicates a known height, like 2 meters. His partners goes about 10 m away, holds out his pencil at arm's length toward the tree, marks with his thumb on the pencil how far is 2 m, and counts 2-m intervals to the top of the tree.
The fast-growing trees, like alder and redwood, are doing about 0.5m/yr. The slow growers include the Pacific Dogwood and oaks.