Scientific Name: Acacia koa
Hawaiian Name: Koa
This iconic plant is known for it’s sickle shaped leaves, but is often confused with Australian eucalypts which is very similar. To tell the difference one can break a leaf and see if it smells like eucalyptus or grass. Hawaiians actually used the elepaio bird to check on how healthy koa trees were before using them for massive voyaging and fighting canoes. If the bird found many insects than the tree was probably bad. On the other hand few insects were a good sign of a sturdy Canoe.
The Koa is the largest tree of native Hawaiian plants. It can grow to over a 100ft tall and 12 ft wide. The tree is recognizable by it’s crescent shaped leaves and lives in wetter areas than it’s smaller cousin the Koa’i. A baby Koa plant actually has 2 different types of leaves, one being the common crescent shape seen on large trees, and the other tiny similar structure to ulei leaves. This is because that the crescent ” leaves” are not actually leaves but stems that produce photosynthesis.( 3rd photo) This is believed to have been a drought adaptation developed during the ice Age.
Koa’s actually give off a distinct aroma because of a bacteria that is present in it’s roots and soils. This bacteria rhizobia helps convert nitrogen into the form it needs. This results in an ammonia like smell given off. Trees with more rhizobia generally are healthier than those without.
The Hawaiians used the bark to stain kapa( bark cloth) red . The Koa’s other uses were surfboards, paddles spears and timber . However, it was never used for bowls because it contained an irremovable resin that left a poor taste in food. Koa is still highly valued today for it’s grain and a large tree could yield $500,000 alone in lumber