One of the largest trees in the forest, Koa wood was used in the old days for canoes, weapons, and other implements requiring hard wood. The close grain and straight trunk made Koa the ideal choice of wood for the hard years of service in salt water that a canoe must tolerate. To the Hawaiian people, who relied on fish as a source of protein, the Koa was a treasured tree. Koa has two types of leaves. Seedlings sprout stems with rows of rounded leaves, and as the sapling matures the typical sickle-shaped leaves evolve.