Garden Closed

The United States Botanic Garden (USBG) is temporarily closed to the public to reduce the risk of transmitting COVID-19 coronavirus.

Whenever possible, the USBG will reschedule public programs and events originally scheduled during the closure period. Please monitor the USBG website for updates to operating status. Many resources can still be accessed online, including educational worksheets and manuals, fact sheets and more, and some of our programs will also be made available online. Find online resources 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.