In 1876–1877, while Greene was an episcopal priest in Yreka, California, he discovered the first specimens of Phlox hirsuta, a small flowering plant found only in that area.
Phlox | Staurogyne hirsuta | Phlox hirsuta | Kiwa hirsuta | Cardamine hirsuta | Battus philenor hirsuta | '''above:''' cherry tree; '''below:''' ''Phlox subulata'' in an ornamental planting at Yachounomori Garden in Tatebayashi, Gunma |