Mount Yonaha is at the center of the Yanbaru forest that spans the villages of Higashi, Kunigami, and Ōgimi. Yanbaru contains some of the last large surviving tracts of subtropical rainforest in Asia, and the mountain is lush with evergreens forests. While Mount Yonaha is an important natural habitat to numerous species of plants, birds, and animals, the ecology of the mountain has been negatively affected by agricultural development at the base of the mountain, and lumbering and the subsequent establishment of second-growth forest.