Garden Closed

Due to the closure of the U.S. Capitol Campus to the public, the U.S. Botanic Garden continues to have altered operations.  Bartholdi Fountain and Gardens and the Terrace Gardens are open while the Conservatory and gated outdoor gardens are temporarily closed. Please monitor for updates on operating status. Many resources can be accessed online, including educational materials, virtual tours, and online programs. Connect with resources from home at

Koa'oha or Koai‘a

Koai‘a or Acacia koaia
Plant Botanical Name: 
Acacia koaia
USBG Plant Location: 
Conservatory Room Location: 
Plant Threat Level: 

The Koa' oha tree is native to Hawaii and can be found on the islands of Kaua'i, O'ahu, Moloka'i, Lana'i, and Maui in dry, lowland habitats. Native Hawaiians used the tree's leaves to make a tea for medical baths, bark to dye cloth and wood for surfboards, paddles, and ukuleles. The dry, lowlands areas that the koaoha favors is also prime location ranching and agriculture. Due to increased agricultural activity, the koa' oha's habitat has decreased substantially as it is additionally threatened by grazing livestock and encroachment of non-native species giving it a "G2" ranking by NatureServe, "Vulnerable" by IUCN, and as a "Species of Concern" by the United States.