Polemonium occidentale
| Polemonium occidentale | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Plantae |
| Clade: | Embryophytes |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Asterids |
| Order: | Ericales |
| Family: | Polemoniaceae |
| Genus: | Polemonium |
| Species: | P. occidentale |
| Binomial name | |
| Polemonium occidentale | |
| Synonyms[2] | |
| |
Polemonium occidentale is a species of flowering plant in the phlox family known by the common names western polemonium[3] and western Jacob's-ladder. There are two subspecies.[4] The common ssp. occidentale is native to western North America from British Columbia to Colorado to California, where it can be found in moist areas of many habitat types, including meadows and woodlands. There is also a rare subspecies, ssp. lacustre, which is known only from a total of three counties in Minnesota and Wisconsin, and is found only in white cedar swamp habitat there.[4]
This is a rhizomatous perennial herb producing an erect stem up to one meter tall. The leaves are located along the stem, each divided into many small lance-shaped leaflets. The inflorescence is an open, elongated array of several bell-shaped, five-lobed flowers each up to 1.5 centimeters long. The flower corolla is blue to bright purple with a white throat.[5]
Taxonomy
Botanist Edward Lee Greene scientifically described Polemonium occidentale in 1890, placing it in the Polemonium genus. Along with its genus it is classified in the Polemoniaceae family.[2] The rare species Polemonium lacustre was initially described as a subspecies of Polemonium occidentale,[6] there are five populations that grow in swamps in Wisconsin and Minnesota.[7] Although it has no accepted subspecies, it has one among its eleven synonyms and has also been described as a subspecies twice.[2]
| Name | Year | Rank | Notes |
|---|---|---|---|
| Polemonium acutiflorum subsp. occidentale (Greene) Hultén | 1948 | subspecies | ≡ hom. |
| Polemonium caeruleum subsp. amygdalinum (Wherry) Munz | 1958 | subspecies | = het. |
| Polemonium caeruleum var. foliosissimum A.Gray | 1870 | variety | = het. |
| Polemonium caeruleum subsp. occidentale (Greene) J.F.Davidson | 1950 | subspecies | ≡ hom. |
| Polemonium caeruleum var. occidentale (Greene) H.St.John | 1956 | variety | ≡ hom. |
| Polemonium caeruleum var. pterospermum Benth. | 1845 | variety | = het. |
| Polemonium helleri Brand | 1907 | species | = het. |
| Polemonium intermedium (Brand) Rydb. | 1913 | species | = het. |
| Polemonium occidentale subsp. amygdalinum Wherry | 1942 | subspecies | = het. |
| Polemonium occidentale var. intermedium Brand | 1907 | variety | = het. |
| Polemonium occidentale subsp. typicum Wherry | 1942 | subspecies | ≡ hom., not validly publ. |
| Notes: ≡ homotypic synonym; = heterotypic synonym | |||
References
- ↑ NatureServe (31 July 2026). "Polemonium occidentale". NatureServe Explorer. Arlington, Virginia. Retrieved 12 August 2026.
- 1 2 3 POWO (2026). "Polemonium occidentale Greene". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 12 August 2026.
- ↑ NRCS. "Polemonium occidentale". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 9 October 2015.
- 1 2 Schmidt, L. J. Conservation Assessment for Polemonium occidentale v. lacustre, Western Jacob's Ladder. USFS. September 2003.
- ↑ "Western Sky Pilot, Polemonium occidentale". calscape.org.
- ↑ POWO (2026). "Polemonium lacustre (Wherry) J.P.Rose & Sytsma". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 12 August 2026.
- ↑ Center for Plant Conservation Archived 2010-10-29 at the Wayback Machine