Kelseya

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Rosids
Cladus: Eurosids I
Ordoo: Rosales

Familia: Rosaceae
Subfamilia: Amygdaloideae
Tribus: Spiraeeae
Genus: Kelseya
Species: K. uniflora
Name

Kelseya Rydb., N. Amer. Fl. 22(3): 254. (1908)

Type species: Kelseya uniflora (S.Watson) Rydb., N. Amer. Fl. 22: 254. (1908)
monotypic taxon

References

Rydberg, P.A. 1908. North American Flora 22(3): 254.
Govaerts, R. et al. 2021. Kelseya in Kew Science Plants of the World online. The Board of Trustees of the Royal Botanic Gardens, Kew. Published online. Accessed: 2021 May 22. Reference page.
Hassler, M. 2021. Kelseya. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2021. Species 2000 & ITIS Catalogue of Life. Published online. Accessed: 2021 May 22. Reference page.
International Plant Names Index. 2021. Kelseya. Published online. Accessed: May 22 2021.
Tropicos.org 2021. Kelseya. Missouri Botanical Garden. Published online. Accessed: 22 May 2021.

Kelseya is a monotypic genus of flowering plants belonging to the family Rosaceae. The only species is Kelseya uniflora.[1] It is commonly called the oneflower kelseya, spiraea or alpine laurel.[2][3] The genus was named in honor of Francis Duncan Kelsey, a Montana resident botanist, who discovered the plant in 1888 at the "Gate of the Mountains" near Townsend.[4][5]

Description

Kelseya uniflora is a perennial limestone endemic[2] that grows in cracks of volcanic and limestone outcrops at 1500-3500m elevation.[6][3] It is native in 3 states in Northwestern USA: Idaho, Montana and Wyoming.[2] It typically grows as a solitary plant in a sun-exposed position as a ground covering subshrub. This species has also been reported in riparian woodland but this should be considered an outlier.[7][8] Their most prolific growth is on the South Summit of Hunt Mountain in the Bighorn Mountains where it grows on Karst features.[9]

This species rarely measures more than 10cm tall but often achieves 1m or more in diameter.[2][6] Their habit is an adaptation to the wind-blast exposed rocky ridges they grow on alongside cushion plant communities.[10] Plants branch into numerous slender stems that are densely covered with imbricated leaves. The leaves are light to greyish green, leathery and hairy, ovate-oblong and grow in dense rosettes. Leaves become brownnish to black when withered and remain on the branch to form a hardened protective structure.[3][6] The branches have fine hairs that collect moisture from cracks in the rock.[9]

The solitary terminal flowers[11] are produced very early in spring and are reddish-purple to pinkish white.[12][9] The flowers typically open as the snow melts back.[13] The 5 sepals are only 2mm long with the 5 petals elliptic to oblong and advertising a shade of pink. The 7 to 12 stamens are slightly longer than the petals.[14]

From very early on it was clear that these plants formed an outlier group within Rosaceae and together with Petrophytum and Eriogynia (now Luetkea) they were treated as sections within the genus Eriogynia.[15] After a number of revisions and molecular analysis they are now member of tribe Spiraeeae.[16][17]

The reduction in plant stature and its xeric alpine habitat make it a popular but challenging subject for alpine garden enthusiasts.[18]
Conservation Status

Kelseya uniflora is reported to have a global NatureServe conservation status of "Secure". Its global status, however dates from 1987 and needs review.[19]

In the three states where it occurs its status is:

Idaho: SNR (No Status Rank)
Montana: S4 (Apparently Secure)
Wyoming: S2 (Imperiled)

In 2006, naturalists from Montana and Wyoming were asked to report their findings on an apparent die-back occurring in local populations of this species. The author also mentioned the same happening with Petrophyton caespitosum, a species that inhabits a similar ecological niche.[13]
References

"Kelseya (S.Watson) Rydb. | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 26 May 2021.
"Kelseya uniflora (S. Watson) Rydb". United States Department of Agriculture. Retrieved 29 July 2021.
"Kelseya uniflora". Flora of North America. Flora of North America Association. Retrieved 29 July 2021.
Lesica, Peter (Winter 2007). "Kelseya uniflora, the MNPS Mascot"" (PDF). Kelseya - Newsletter of the Montana Native Plant Society. 4 (1): 1. Retrieved 30 July 2021.
Proceedings of the American Academy of Arts and Sciences, Volume 25. Metcalf and Company. 1890. p. 130. Retrieved 2 August 2021.
"Kelseya uniflora". The Alpine Garden Society Plant Encyclopedia. The Alpine Garden Society. Retrieved 29 July 2021.
Bighorn Canyon National Recreation Area (N.R.A.), General Management Plan (GMP) and Wilderness Recommendation (MT,WY). U.S. Department of the Interior. 1981. p. 93. Retrieved 2 August 2021.
Johnson, Tim (23 July 2019). CRC Ethnobotany Desk Reference. CRC Press. p. 56. ISBN 9781351087841. Retrieved 2 August 2021.
"Kelseya uniflora". Mountain Flora Hikes. Mountain Flora Hikes. Retrieved 4 August 2021.
Locklear, James H. (9 March 2011). Phlox: A Natural History and Gardener's Guide. Timber Press. p. 223. ISBN 9780881929348. Retrieved 2 August 2021.
"One-flower Kelseya - Kelseya uniflora". Montana Field Guide. Montana Natural Heritage Program. Retrieved 5 August 2021.
Ahlenslager, Kathy (Winter 2007). "Kelseya uniflora" (PDF). Kelseya. Retrieved 2 August 2021.
McCracken, Clayton (Summer 2006). "Is the Kelseya dying?" (PDF). Kelseya. 19 (4): 3–4.
Lis, Richard. "Kelseya Rydberg in N. L. Britton et al". Flora of North America. Retrieved 5 August 2021.
Proceedings of the American Academy of Arts and Sciences, Volume 25. Metcalf and Company. 1890. p. 131. Retrieved 2 August 2021.
Potter, Dan; Still, Shannon (Winter 2007). "Phylogenetic position of Kelseya based on molecular data" (PDF). Kelseya. Retrieved 2 August 2021.
Dan, Potter (2007). "Phylogeny and classification of Rosaceae". Plant Systematics and Evolution. 266 (1–2): 5–43. doi:10.1007/s00606-007-0539-9. S2CID 16578516.
R. Kruckeberg, Arthur; Chalker-Scott, Linda (12 March 2019). Gardening with Native Plants of the Pacific Northwest (3 ed.). University of Washington Press. p. 273. ISBN 9780295744865. Retrieved 2 August 2021.
"Kelseya uniflora". NatureServe. NatureServe. Retrieved 4 August 2021.