- Ledum
Taxobox
name = "Rhododendron" subsect. "Ledum"
image_width = 240px
image_caption = "Rhododendron tomentosum" ("Ledum palustre")
regnum =Plant ae
divisio = Magnoliophyta
classis =Magnoliopsida
ordo =Ericales
familia =Ericaceae
genus = "Rhododendron "
subsectio = "Ledum"
subdivision_ranks = Species
subdivision = See text."Ledum" is a
genus name formerly widely recognised in the familyEricaceae , including 8 species ofevergreen shrub s native to cool temperate and subarctic regions of theNorthern Hemisphere and commonly known as Labrador Tea.Recent genetic evidence has shown that the species previously treated in this genus are correctly placed in the genus "
Rhododendron ", where they are now treated as "Rhododendron" subsect. "Ledum".Because some of the species names used in "Ledum" could not be used in "Rhododendron" (the names already having been used for other species already in this large genus), new names had to be coined for them.
;SpeciesThe species formerly listed in "Ledum", with their current accepted names in "Rhododendron", are:
*"Ledum decumbens" = "Rhododendron subarcticum " Harmaja
*"Ledum glandulosum" = "Rhododendron neoglandulosum " Harmaja
*"Ledum groenlandicum" = "Rhododendron groenlandicum " (Oeder) Kron & Judd
*"Ledum hypoleucum" = "Rhododendron hypoleucum " (Kom.) Harmaja
*"Ledum macrophyllum" = "Rhododendron tolmachevii " Harmaja
*"Ledum palustre" = "Rhododendron tomentosum " Harmaja
*"Ledum palustre" var. "diversipilosum" = "Rhododendron diversipilosum " (Nakai) Harmaja
*"Ledum subulatum" = "Rhododendron subulatum " (Nakai) Harmaja;HybridsOne natural hybrid also occurs:
*"Ledum columbianum" = "Rhododendron × columbianum" ("R. groenlandicum" × "R. neoglandulosum")Uses
Some species (e.g. "L. groenlandicum") have been used to produce
Labrador Tea . Other species have varying levels of toxicity (e.g. "L. glandulosum"). Evergreen Labrador Tea grows slowly, but retains its leaves year-round. Users should take care not to over-harvest leaves from any single plant."Ledum" sp. often grows together with poisonous plants such as
Bog-laurel andBog-rosemary , but certain species (e.g. "L. groenlandicum" and "L. palustre") are easily distinguished by the distinctive rust coloured fuzz on the bottom of leaves.References
1. Kron, Kathleen A. & Judd, Walter S. (1990) Phylogenetic Relationships within the Rhodoreae (Ericaceae) with Specific Comments on the Placement of "Ledum" Systematic Botany (1990), 1S(1): pp. S7-68
2. Harmaja, Harri (1990) New names and nomenclatural combinations in "Rhododendron" (Ericaceae) Ann. Bot. Fennici 27:203-204
3. Harmaja, Harri (1991) Taxonomic notes on "Rhododendron" subsection Ledum ("Ledum", Ericaceae), with a key to its species. "Ann. Bot. Fennici" 28: 171-173.
[http://www.sekj.org/PDF/anbf35/anbf35-263p.pdf 4. Harmaja, Harri (1999) "Rhododendron diversipilosum", comb. nov. (Ericaceae). Ann. Bot. Fennici 35: 263-264]
[http://www.sekj.org/PDF/anb39-free/anb39-183s.pdf 5. Harmaja, Harri (2002) "Rhododendron subulatum", comb. nova (Ericaceae). Ann. Bot. Fennici 39: 183-184]
6. Kihlman, Bengt A. (2004) Hybrids Between Ledums and Lepidote Rhododendrons. Journal of the American Rhododendron Society 58(2):74-81
Wikimedia Foundation. 2010.