Koa
Acacia koa
Also known as: Hawaiian Koa, Koa Acacia
Koa is Hawaii's most prized native wood, renowned for its stunning figure and importance in ukulele and guitar making. Its golden to reddish-brown color and often spectacular curl make it highly sought after. The species is endemic to Hawaii with limited supply, making it a precious and protected resource.
Botanical Profile
Acacia koa is a large leguminous tree endemic to the Hawaiian Islands, typically reaching 15-25 meters in height. It grows in mesic to wet forests at mid-elevation and has distinctive sickle-shaped foliage. The tree is a nitrogen-fixer that plays a crucial role in native forest ecology.
Physical Properties
The heartwood ranges from golden to reddish-brown, often with dramatic curl, fiddleback, or feather figure. It has a medium texture with straight to wavy grain. Dried weight averages 610 kg/m³ with a Janka hardness of 1,170 lbf. The wood is moderately dense with excellent acoustic properties.
Workshop Notes
Blunting Effect
Moderate
Gluing Advice
Good gluing properties
Finishing
Excellent - takes oil and polish beautifully, figure enhances with finish
Steam Bending
Good steam bending characteristics
Historical Context
Koa was used by Hawaiian royalty for canoes, surfboards, and sacred objects. It became famous for ukuleles when the instrument spread from Hawaii in the early 20th century. Today it remains central to Hawaiian cultural identity and the premium instrument market, with strict harvesting regulations.
Technical Specs
Golden to reddish-brown heartwood with striking figure, pale sapwood
Vulnerable - endemic to Hawaii, limited supply, protected