Virginia Tech Dendrology

koa Fabaceae Acacia koa A. Gray symbol: ACKO
Leaf: Alternate, deciduous, bipinnately compound, 2 to 10 inches long, with 2 to 8 pairs of major leaflets and 15 to 25 pairs of minor leaflets, green to grayish green and somewhat leathery. The petioles may become flat and more than 1 inch wide, forming leathery phyllodes that are oval to sickle-shaped with parallel venation. Phyllodes may or may not bear bipinnate leaflets.
Flower: Species is monoecious; yellow to white in showy round axillary racemes that are up to 1/3 inch in diameter, appearing throughout the year but most common in late winter.
Fruit: A 6 to 12 inch long by 1/2 inch wide flattened bean pod containing 6-12 seeds; initially green, ripening to dark brown; ripening throughout the year.
Twig: Zigzag, slender, initially green but aging to gray-brown; lacking thorns or spines.
Bark: Variable; initially reddish brown and smooth, becoming irregularly ridged and furrowed, eventually becoming pale and somewhat scaly.
Form: Potentially a large tree capable of reaching 100 feet tall, most often a smaller tree with a crooked bole; widely spreading when open-grown.

Additional Range Information: Acacia koa is native to North America. Range may be expanded by planting. Download the full-size PDF map.
External Links: USDAFS Silvics of North America - USDA Plants Database
All material 2021 Virginia Tech Dept. of Forest Resources and Environmental Conservation; Photos and text by: John Seiler, Edward Jensen, Alex Niemiera, and John Peterson; Silvics reprinted from Ag Handbook 654; range map source information