Rhododendron minus |
Rhododendron columbianum |
|||||
---|---|---|---|---|---|---|
Piedmont rhododendron |
Mt. Labrador tea, smooth Labrador tea, trapper's-tea, western Labrador tea |
|||||
Habit | Shrubs, to 3(–5) mm, often rhizomatous. | Shrubs or trees, to 2 m, rhizomatous. | ||||
Stems | bark smooth to vertically furrowed, shredding; twigs with ferrugineous, multicellular, broad-rimmed, glandular-peltate scales. |
bark smooth, sometimes peeling or shredding with age; twigs unicellular-hairy, papillate, with flattened, glandular scales (lepidote). |
||||
Leaves | persistent; petiole with ferruginous, broad-rimmed, glandular-peltate scales and unicellular-hairy; blade narrowly elliptic to elliptic or oval, sometimes obovate, (1–)5–8(–13) × (1–)2–3.5(–5.5) cm, thick, coriaceous, margins entire, plane to conspicuously revolute, with scattered, glandular-peltate scales, apex acute or acuminate or obtuse to rounded, surfaces with scattered, ferruginous, broad-rimmed, glandular-peltate scales abaxially, (scales ± deciduous adaxially). |
persistent, (fragrant when crushed); petiole with glandular-peltate scales without broad rim and few, ferruginous, long-crisped hairs; blade (white or pale green abaxially), ovate to lanceolate, (1–)2–8 × 1.5–3 cm, coriaceous, margins entire, plane, glabrous, apex usually acute, abaxial surface sparsely to densely papillate, with few, ferruginous, long-crisped hairs and glandular-peltate scales without broad rim, adaxial surface with scattered lepidote scales and/or papillae, sometimes also unicellular-hairy along midrib. |
||||
Inflorescences | 5–10-flowered; bracts similar to bud scales. |
slightly rounded, 10–35-flowered; bracts lepidote abaxially, margins ciliate, unicellular-hairy. |
||||
Pedicels | 5–15 mm, with ferruginous scales. |
4–25 mm, with dense to sparse, ferruginous, long-crisped, unicellular and/or peltate scales, sometimes also long-stalked, multicellular glandular-hairy. |
||||
Flowers | opening before or after development of leaves, erect to horizontal, fragrant; calyx lobes 0.5–2 mm, with ferruginous scales; corolla dark to very pale pink or white, upper lobe usually with greenish spots, campanulate to funnelform, 15–37 mm, with scattered, ferruginous, peltate scales on outer surface, petals connate (for 3/4+ their lengths), lobes 8–19 mm, tube gradually expanding into lobes, 8–22 mm; stamens 10, included to slightly exserted, ± unequal, 13–26 mm. |
radially symmetric, opening after leaves (of flowering shoots), ± erect, fragrance not noticeable at mid day; calyx lobes (often reflexed in fruit), ± 1–1.5 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 hairy proximally, outer surface glabrous, petals appearing distinct or only slightly connate basally, lobes (4–)5–7 mm; stamens (8–)10(–12), exserted, ± equal, 4.5–8.4 mm. |
||||
Capsules | borne on erect pedicels, 6–14 × 2.9–5 mm, with ferruginous, peltate scales. |
borne on recurved pedicels, 2.5–5 × 2–6 mm (only slightly longer than wide), glabrous, acropetally dehiscent. |
||||
Seeds | with short, blunt/truncate tails at each end; testa closely appressed. |
somewhat elongated beyond narrow ends; testa closely appressed. |
||||
Floral | bud scales ferruginous-lepidote, sometimes also unicellular-hairy abaxially, margins unicellular-ciliate. |
bud scales with peltate scales without broad rim and unicellular-hairy abaxially, margins unicellular-hairy. |
||||
2n | = 26. |
= 26. |
||||
Rhododendron minus |
Rhododendron columbianum |
|||||
Phenology | Flowering spring-mid summer. | |||||
Habitat | Bogs, swamps, stream margins, sometimes on well-drained sites | |||||
Elevation | 0-3500 m (0-11500 ft) | |||||
Distribution |
AL; FL; GA; NC; SC; TN
|
CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC
|
||||
Discussion | Varieties 2 (2 in the flora). Rhododendron minus is here circumscribed broadly, including R. carolinianum and R. chapmanii, and the latter is considered to be a distinct variety (W. H. Duncan and T. M. Pullen 1962). Variety chapmanii is federally listed. This species is often grown as an ornamental. Rhododendron minus and R. lapponicum are members of subg. Rhododendron, as indicated by their glandular-peltate scales; the subgenus is represented by hundreds of species in eastern and southern Asia (see J. Cullen 1980). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|||||
Key |
|
|||||
Source | FNA vol. 8, p. 460. | FNA vol. 8, p. 459. | ||||
Parent taxa | Ericaceae > subfam. Ericoideae > Rhododendron | Ericaceae > subfam. Ericoideae > Rhododendron | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Ledum columbianum, Ledum glandulosum, R. neoglandulosum | |||||
Name authority | Michaux: J. Hist. Nat. 1: 412. 1792 , | (Piper) Harmaja: Ann. Bot. Fenn. 27: 203. (1990) | ||||
Web links |
|