Sophora chrysophylla aka Mamani

Sophora chrysophylla, or mamane, belongs to the pea family, Fabaceae. It is native to the Hawaiian Islands. It grows in dry scrub and forests with varied moisture levels. It also reaches wet forests, though these sites are rare. Its range extends from near sea level into high mountains. Most records fall between 1,476 and 10,630 feet [450–3,240 metres].

Its size and form change with its site. At lower heights, trees reach 20–49 feet [6–15 metres]. Poor soil and high sites can keep plants shrub-sized. These shrubs may stand just 3.3 feet [1 metre] tall. Trunks can reach 2 feet [0.6 metres] across. Young bark is smooth, with an orange-brown tone. It turns gray and rough with age. The stout, ridged twigs are yellow-green. Sources differ on whether the leaves persist or fall. Virginia Tech calls them evergreen; Useful Tropical Plants calls them deciduous.

The alternate leaves are pinnate, with five to eleven leaflets. Each leaflet has an oval or broad, stretched shape. Their firm, leathery blades are gray-green on top. Pale hairs cover the lower surface. Bright yellow flowers form long clusters at shoot tips or leaf joints. Flowers appear when conditions suit growth, rather than in a stated season. The fruit is a woody legume with a ridged shell. Each pod narrows between its seeds and stays on the plant. Pods shift from green to gray-brown as they age. They hold one to five bright orange seeds.

Mamane needs a sunny growing site and develops deep roots. Bacteria in root nodules help it obtain nitrogen from the air. Some of this nitrogen can also support nearby plants. Seeds need treatment before sowing. Soak them in warm water for 12–24 hours. If they fail to swell, gently wear down the seed coat. Avoid harming the seed inside. Sow treated seeds in part shade. Sprouts may appear within one to two weeks.

The yellow flowers provide the plant's main showy feature. People harvest wild trees for their hard wood. The wood lasts well in soil and serves as fence posts. Other uses include thatching poles, sledge runners, and fuel. Useful Tropical Plants lists no known food or medicinal uses. It also lists no known hazards, but this does not establish safety.