Gastrodia is a genus of achlorophyllous orchid with 61 currently accepted species (as of June 2014). They are native to Asia (China, the Russian Far East, Japan, Korea, Southeast Asia, the Indian Subcontinent), Australia, New Zealand, central Africa, and various islands of the Indian and Pacific Oceans. Gastrodia elata is a traditional Chinese herb, Tian Ma (Chinese: 天麻)， and is commonly used in China to treat hypertension, improve circulation and resolve headaches.