Acacia koa is a tree that can grow up to 35 meters tall. The leaves of juvenile plants are compound bipinnate, but as the plant matures, the leaves are simplified into phyllodes of petiolar origin, which are narrowly elliptic, strongly falcate, and range from 7.5 to 26 cm in length and 0.5 to 2.5 cm in width. These phyllodes have entire margins and are often equipped with extrafloral glands on the leaf rachises. It lacks stipules, and its leaves are arranged alternately. Its flowers are small, about 2 mm long, cream-colored, and mimosaceous, appearing in heads about 8 mm in diameter, grouped in axillary racemes or sometimes in terminal leafy panicles. The flowers have numerous curled stamens that are significantly longer than the corolla, producing the pollen in tetrads. The fruit is a flattened pod, oblong in shape, ranging from 8 to 30 cm in length and 0.8 to 2.5 cm in width, containing ellipsoid, laterally flattened seeds that are arranged either transversely or longitudinally; 6-12 mm long, 4-7 mm wide. It is found in dry to moist forests from 60 – 2,060 meters, occasionally as low as 25 meters, and rarely as high as 2,450 meters.
Bean-shaped (Reniform): Resembling the shape of a kidney or bean.
Square or Oblong: Angular shape with all sides more or less equal or longer than wide.
Triangular: Three-sided shape, broadest below the middle.
Elliptic: Rounded at both ends. shaped like an ellipse or oval.
Ovate or Obovate: egg-shaped, broader at one end.
Linear: Extremely long and narrow, with sides usually parallel.
Round: Appears circular, with length and width roughly the same.
Cardioid (Heart-Shaped): One edge has a prominent double curve into two lobes.
Cylindrical: A cylinder with parallel sides and a circular cross-section.
Discoid: Resembling a disc or plate with two relatively flat surfaces.
Fusiform: Spindle-shaped, tapering at both ends.
Globose: Spherical.
Lenticular: Resembling a lens with two convex surfaces.
Ovoid: Egg-shaped.
Plano-convex: Having a flat ventral (planar) surface and a curved dorsal (convex) surface.
Polygonal: Having more than three flat faces meeting at angles.
Sectoroid: Resembling a segment of an orange with two relatively flat faces and one curved face.
Subglobose/ellipsoid: Inflated shape but less than spherical.
Trigonous: Having three faces that meet at a distinct angle; triangular in cross-section.
Endangered species (E) are species that are so rare they’re in danger of becoming extinct.
Threatened species (T) are species that are likely to become endangered within the foreseeable future throughout all or a significant portion of their range.
Species of Concern (SOC) are species about which there are some concerns regarding status and threats, but insufficient information is available to list the species under the Endangered Species Act (ESA).
Plant Extinction Prevention (PEP) is a state status for rare plants that focuses its efforts on species that have fewer than 50 remaining wild individuals.
Orthodox seeds (desiccation-tolerant): can be dried to an internal seed moisture of less than 12% water and stored at freezing temperatures.
Intermediate seeds (temperature-sensitive) tend to age faster than orthodox seeds and may have only a 5-year lifespan when stored at -20°C. They are recommended for storage at 5°C.
Recalcitrant seeds (desiccation-sensitive): cannot be stored in a conventional freezer as they cannot survive after drying and/or freezing at -20°C. They are recommended for cryopreservation storage.