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mountain azalea, Piedmont or southern pinxterbloom azalea

Habit Shrubs or trees, to 6 m, usually not rhizomatous. Subshrubs, shrubs, or trees, multicellular hairs present; bark smooth or furrowed, not flaky (peeling or shredding in Menziesia).
Stems

bark smooth to vertically furrowed, shredding;

twigs scattered, multicellular eglandular- and/or stipitate-glandular-hairy (hairs unbranched), otherwise moderately to densely unicellular-hairy.

erect to decumbent, sprawling, creeping, trailing, prostrate, or procumbent.

Leaves

deciduous;

petiole usually multicellular eglandular- or stipitate-glandular-hairy, also unicellular-hairy;

blade ovate to obovate, 2.5–10(–13) × 1.2–3(–4) cm, thin, membranous to chartaceous, margins entire, rarely minutely serrulate, plane, inconspicuously ciliate, eglandular-hairy (hairs appressed to margins), apex acute to obtuse, often mucronate, abaxial surface densely to sparsely unicellular-hairy, sometimes glabrous or glabrate, often also scattered eglandular-hairy, adaxial surface usually scattered eglandular-hairy, otherwise sparsely unicellular-hairy, sometimes glabrous.

deciduous or persistent, usually alternate, sometimes opposite, whorled, or spirally arranged;

petiole usually present;

blade plane or acicular, abaxial groove present or absent.

Inflorescences

6–19-flowered;

bracts similar to bud scales.

axillary or terminal, fascicles, racemes, panicles, capitula, cymes, umbels, corymbs, spikes, or solitary flowers;

perulae present or absent;

bracts much shorter than sepals (sometimes absent).

Pedicels

4–17 mm, usually eglandular-hairy, rarely stipitate-glandular- and/or eglandular-hairy, otherwise sparsely to densely unicellular-hairy.

Flowers

opening before or with leaves, erect to horizontal, fragrant (usually musky-scented);

calyx lobes 0.5–4 mm, surfaces and margins scattered stipitate-glandular- and/or eglandular-hairy, otherwise usually densely unicellular-hairy;

corolla deep pink to white with pink tube, without blotch on upper lobe, funnelform, 23–46 mm, scattered, multicellular stipitate-glandular-hairy (hairs not forming distinct lines), otherwise sparsely to densely unicellular-hairy on outer surface, petals connate, lobes 7–20 mm, tube ± gradually expanded into lobes, 13–27 mm (equaling or longer than lobes);

stamens 5, much exserted, ± unequal, 31–64 mm.

bisexual or unisexual, erect or pendulous, usually radially or bilaterally symmetric;

sepals (2-)4-5(-7);

petals absent or (2-)4-5(-7), connate or distinct, corolla deciduous or persistent, campanulate, salverform, rotate, saucer-shaped, funnelform, cylindric, or urceolate, (with pockets holding anthers until they open in some Kalmia), lobes shorter than tube;

intrastaminal nectary disc present;

stamens (2-)5-10;

anthers dehiscent by lateral pores or slits;

ovary (2-)5-10-locular;

placentation axile (parietal distally in Epigaea);

style straight or declinate (curved in Elliottia).

Fruits

capsular, dehiscence usually septicidal, sometimes loculicidal or septifragal, or drupaceous, (dry to fleshy), indehiscent.

Capsules

borne on erect pedicels, 12–33 × 3–6.5 mm, usually sparsely to moderately eglandular-hairy, otherwise ± densely unicellular-hairy.

Seeds

without distinct tails, flattened portion of testa well developed at each end;

testa expanded, dorsiventrally flattened, ± loose.

2-300, distinct, obovoid, ovoid, or ellipsoid to oblong, linear, fusiform, or planoconvex, winged or not.

Floral

bud scales ± densely unicellular-hairy abaxially, margins usually unicellular-ciliate.

2n

= 26.

Rhododendron canescens

Ericaceae subfam. ericoideae

Phenology Flowering spring.
Habitat Moist to dry woods, pocosins, swamps and savannas, often along streams
Elevation 0-500 m (0-1600 ft)
Distribution
from FNA
AL; AR; FL; GA; IL; KY; LA; MS; NC; OK; SC; TN; TX
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North America; Mexico; Central America; West Indies (Cuba); s South America; Europe; Asia; Africa; Atlantic Islands; Australia; especially diverse in western Europe and southern Africa
Discussion

Rhododendron canescens is most similar to R. prinophyllum and R. periclymenoides, although these three species do not constitute a clade (K. A. Kron 1993); they occasionally hybridize where their habitats and ranges overlap. In addition, putative hybrids with R. alabamense, R. atlanticum, R. austrinum, R. flammeum, R. periclymenoides, and R. calendulaceum are known.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Genera 18, species ca. 1850 (14 genera, 58 species in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 8, p. 469. FNA vol. 8, p. 449. Authors: Gordon C. Tucker, Gary D. Wallace.
Parent taxa Ericaceae > subfam. Ericoideae > Rhododendron Ericaceae
Sibling taxa
R. alabamense, R. albiflorum, R. arborescens, R. atlanticum, R. austrinum, R. calendulaceum, R. canadense, R. catawbiense, R. columbianum, R. cumberlandense, R. eastmanii, R. flammeum, R. groenlandicum, R. lapponicum, R. macrophyllum, R. maximum, R. minus, R. occidentale, R. periclymenoides, R. prinophyllum, R. prunifolium, R. tomentosum, R. vaseyi, R. viscosum
Subordinate taxa
Synonyms Azalea canescens, Azalea candida tribe Empetraceae
Name authority (Michaux) Sweet: Hort. Brit. ed. 2, 343. 1830 , Link: Handbuch 1 602. (1829) — (as Ericeae)
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