[W. americana L.; W. indica var. americana (L.) Hosaka; W. pyrolaefolia A. Gray]
(ind?) ‘Uhaloa, ‘ala ‘ala pu loa, hala ‘uhaloa, hi‘aloa, kanakaloa
Subshrubs 6-20 dm tall; stems rather rigid, erect to sometimes decumbent, velvety tomentose throughout, the hairs stellate. Leaves rugose, broadly ovate to oblong-ovate, 2-15.5 cm long, 1-6 cm wide, tomentose with stellate hairs, lower surface paler, apex rounded, sometimes obtuse, base rounded to subcordate, petioles 0.5-4.5 cm long. Flowers fragrant, in axillary, sessile or pedunculate glomerules, bracts linear; calyx strongly ribbed, ca. 3-5 mm long, villous; petals yellow, spatulate, 4-6 mm long; style bearded. Capsules obliquely globose, 2.5-3 mm long. [2n = 14, 26, 40.] Pantropical; in Hawaii apparently indigenous, occurring in dry, often disturbed sites, 0-1,220 m, on Midway Atoll and all of the main islands. First noted in Hawaii by D. Nelson in 1779 (St. John, 1978e).— Plate 187.
This plant was used medicinally by the Hawaiians; the bitter inner bark or roots apparently worked as a pain killer especially for sore throat (Neal, 1965; Pukui & Elbert, 1986). Waltheria pyrolaefolia apparently was described for an aberrant leaf form of one collection made by the U.S. Exploring Expedition, and was reduced to synonymy by St. John (1976g).