Hao (Rauvolfia sandwicensis)

Photo courtesy of MNBG

Hawaiian name: Hao (Haa)
Botanical name: Rauvolfia sandwicensis
Family: Apocynaceae (Plumeria Family)
Status: Endemic
Where found: Maui, Moloka‘i, Lāna‘i, Hawai‘i, O‘ahu, Ni‘ihau & Kaua‘i (Hi exc. Ka)
Water/Light: Dry to wet, with full sun exposure
Elevation range: 0 to 2,600 feet
Height: 20 feet with a 15 foot spread

Hao (not to be confused with hau, Taliparti tiliaceum) produces tiny flowers with a fragrance similar to Plumeria, which belong to the same family. The beloved lei plant maile (Alyxia stellata) is also in this family. The Hawaiian word for iron or iron tools is also hao, and the wood was used in construction in ancient times, but various sources disagree on whether hao wood is hard, moderately hard, or soft. Remnants of this native tree have been found at many ancient heiau (alters) throughout Hawai‘i. Leading historians to believe it was used within religious ceremonies. A slow growing tree that likes full sun, hao was once found in mesic and even wet areas. It is now rare in the wild, with remnant trees still persisting in dry leeward areas on Maui. It is listed by the IUCN (International Union for Conservation of Nature) as Vulnerable. According to Koebele and Eickhoff at their website Native Plants of Hawaiʻi, there are conflicting reports on whether the wood was used as firewood or not. They theorize that may be because this plant contains the alkaloid reserpine, which slows the heartbeat and dilates blood vessels, so the wood smoke may be harmful when burned for fuel.