Rhododendron tomentosum


Ann. Bot. Fenn. 27: 204. 1990,.

Common names: Labrador or trappers tea
Basionym: Ledum palustre Linnaeus Sp. Pl. 1: 391. 1753,
Synonyms: Ledum decumbens (Aiton) Loddiges ex Steudel Ledum palustre subsp. decumbens (Aiton) Hultén Rhododendron subarcticum Harmaja Rhododendron tolmachevii Rhododendron tomentosum subsp. decumbens (Aiton) Elven & D. F. Murray Rhododendron tomentosum var. subarcticum (Harmaja) G. D. Wallace
Treatment appears in FNA Volume 8. Treatment on page 459. Mentioned on page 455, 457, 460, 462.

Shrubs, to 0.5 m, rhizomatous. Stems creeping or prostrate; bark ± smooth; twigs unicellular-hairy and with flattened, glandular scales, scales often obscured by dense, ferruginous, long-crisped, multicellular hairs. Leaves persistent, (fragrant when crushed); petiole with unicellular and/or peltate scales and, sometimes, ferruginous, long-crisped hairs; blade ± linear, 2–5 × 1–4 cm (often much longer than wide), coriaceous, margins entire, revolute, glabrous, apex acute, abaxial surface with sparse to dense, glandular-peltate scales without broad rim, scales often obscured by dense (to sparse), ferruginous, long-crisped, multicellular hairs sometimes forming dense, ± uniform mat, adaxial surface rugose with scattered, lepidote scales and sometimes also with white, unicellular hairs along impressed midrib, midrib usually lanate. Floral bud scales with lepidote scales and unicellular-hairy abaxially, margins unicellular-hairy. Inflorescences slightly rounded, 10–35-flowered; bracts lepidote abaxially, margins ciliate, long-crisped-hairy, sometimes also unicellular-hairy. Pedicels 5–26 mm, sparsely eglandular-hairy (hairs ferruginous, elongated), with ferruginous, long-crisped, unicellular and/or peltate scales, sometimes also long-stalked, multicellular glandular-hairy. Flowers radially symmetric, opening after leaves (of flowering shoots), ± erect, not fragrant; calyx lobes ca. 1 mm, outer surface densely to sparsely unicellular-hairy (hairs tan), and multicellular, stipitate-glandular-hairy (hairs red) on margins; corolla white to cream, without blotch, ± rotate, 2–8 mm, inner surface often densely unicellular-hairy, petals appearing distinct or only slightly connate basally, lobes 5–7 mm; stamens 10, exserted, ± equal, 4.4–8.5 mm. Capsules borne on apex of sharply recurved pedicels, 2.5–5 × 1–3 mm (only slightly longer than wide), with sparse to dense, lepidote scales, acropetally dehiscent. Seeds somewhat elongated beyond narrow ends; testa closely appressed. 2n = 26, 52.

Phenology: Flowering spring–summer.
Habitat: Bogs, muskeg, tundra, raised beach ridges
Elevation: 0-1800 m


V8 898-distribution-map.gif

Greenland, Alta., B.C., Man., Nfld. and Labr. (Nfld.), N.W.T., Nunavut, Ont., Que., Sask., Yukon, Alaska, Europe, Asia.


Selected References


Lower Taxa

... more about "Rhododendron tomentosum"
Walter S. Judd +  and Kathleen A. Kron +
Harmaja +
Ledum palustre +
Labrador or trappers tea +
Greenland +, Alta. +, B.C. +, Man. +, Nfld. and Labr. (Nfld.) +, N.W.T. +, Nunavut +, Ont. +, Que. +, Sask. +, Yukon +, Alaska +, Europe +  and Asia. +
0-1800 m +
Bogs, muskeg, tundra, raised beach ridges +
Flowering spring–summer. +
Ann. Bot. Fenn. +
Ledum decumbens +, Ledum palustre subsp. decumbens +, Rhododendron subarcticum +, Rhododendron tolmachevii +, Rhododendron tomentosum subsp. decumbens +  and Rhododendron tomentosum var. subarcticum +
Rhododendron tomentosum +
Rhododendron +
species +