Koa is a large native tree endemic to Hawai’i. Along with ohi’a, koa dominates the upper levels of the native forest. It can grow to massive proportions, more than 100 feet tall with a diameter of over three feet. A standout tree, koa radiates a silver-green hue off its sickle-shaped leaves. However, these are not true leaves. Instead, Koa produces pinnately compound leaves as a juvenile, which are shed with age, and their stem (phyllodes) flattens out.
A member of the pea family, koa is a nitrogen-fixing tree. This species grows best at higher elevations. It grows rapidly, up to 5 feet a year.
It is essential not to wound the trees, especially in cultivation. Weedwackers and other lawn equipment can ding the tree and create a gaping hole, a place for disease to enter the tree.
The wood is highly prized.
Germination by seed. Some suggest scarification using nail clippers or sandpaper before germinating. Others recommend soaking the seeds in boiling overnight to prepare the seeds. Germination should occur in 7 to 28 days. Seed store well.
- Cultural significance
- Erosion control
- Lei flower
- Nitrogen fixer
- Privacy / screening
- No dangers