Rauvolfia sandwicensis, the devil's-pepper, also known as hao in the Hawaiian language, is a species of flowering plant in the milkweed family, Apocynaceae, that is endemic to Hawaii. It is a shrub, a small tree reaching 6m (20feet) in height, or, rarely, a medium-sized tree up to 12m (39feet) tall with a trunk diameter of 0.3m (01feet).[1] Hao inhabits coastal mesic and mixed mesic forests at elevations of 100–.[2]