| Family | Ericaceae (also placed in Pyrolaceae) |
| Subfamily | Monotropoideae |
| Tribe | Pyroleae |
| Scientific name | Orthilia secunda (L.) House |
| Synonyms | Actinocyclus secundus (L.) Klotzsch; Actinocyclus secundus (L.) Klotzsch var. elatior Lange; Orthilia elatior (Lange) House; Orthilia parvifolia Rafinesque; Orthilia secunda (L.) House subsp. obtusata (Turczaninow) Böcher; Orthilia secunda (L.) House var. obtusata (Turczaninow) House; Pyrola elatior (Lange) Lundell; Pyrola secunda L.; Pyrola secunda L. subsp. obtusata (Turczaninow) Hultén; Pyrola secunda L. var. obtusata Turczaninow; Pyrola secunda L. var. vulgaris Turczaninow; Ramischia elatior (Lange) Rydberg; Ramischia obtusata (Turczaninow) Freyn; Ramischia secunda (L.) Garcke; Ramischia secunda (L.) Garcke forma angustata Andres; Ramischia secunda (L.) Garcke forma serrata Andres; Ramischia secunda (L.) Garcke subsp. obtusata (Turczaninow) Andres; Ramischia secunda (L.) Garcke var. elatior (Lange) Andres; Ramischia secundiflora Opiz; Ramischia secundiflora Opiz var. borealis Čelakovský |
| Common name | (Japanese common name) ko-ichi-yaku-sou (コイチヤクソウ, 小一薬草 [meaning: small ichi-yaku-sou (ichi-yaku-sou = Pyrola japonica)]) |
| (English common name) sidebells wintergreen, one-sided wintergreen | |
| Distribution | (Japan) Hokkaido, Honshu (north of Central region) |
| (Other nations) Russia, Korea, China, Mongolia, Kazakhstan, Kyrgyzstan, Caucasus, Europe, Canada, USA, Mexico, Guatemala | |
| Habitat | Subalpine needleleaf trees forest. |
| Chromosomal number | 2n=38 |
| Description | Plants 10-25cm tall. Leaves 1.5-3cm long, 1-2.5cm wide, pedicels 1-1.5cm long. Flowers pale green ca. 5mm across, flowering in July to August. Seeds 4mm long. Evergreen. Perennial plants. |
| Reference | Orthilia secunda (L.) House |
| Orthilia secunda (L.) House | |
| Orthilia secunda (Linnaeus) House | |
| Orthilia secunda (L.) House | |
| Range-edge effects promote clonal growth in peripheral populations of the one-sided wintergreen Orthilia secunda | |
| Insect repellent coating and industrial product using the same (US Patent Application 20060177472) |
| July 2009 at Mt. Fuji |
July 2009 at Mt. Fuji |
July 2009 at Mt. Fuji |
| July 2009 at Mt. Fuji |
July 2009 at Mt. Fuji |
| July 2009 at Mt. Fuji |