15. Rhododendron alabamense Rehder in E. H. Wilson and A. J. Rehder, Monogr. Azaleas. 141. 1921.
Alabama azalea Alabama azalea
Azalea alabamensis (Rehder) Ashe
Shrubs, to 3(-5) m, usually not rhizomatous. Stems: bark smooth to vertically furrowed, shredding; twigs scattered, multicellular eglandular-hairy (hairs unbranched), otherwise glabrous or moderately unicellular-hairy. Leaves decid-uous; petiole unicellular- and stipitate-glandular-hairy; blade ovate to obovate, 4-7.7(-9.4) × 1.2-2.5(-3.3) cm, thin, membranous, margins entire, plane, ciliate, eglandular-hairy, apex acute to obtuse, often mucronate, abaxial surface glabrous or unicellular-hairy, adaxial surface usually scattered eglandular-hairy, usually also unicellular-hairy. Floral bud scales glabrous or glabrate abaxially, margins unicellular-ciliate. Inflorescences 6-7-flowered; bracts similar to bud scales. Pedicels 4-12 mm, eglandular- and/or stipitate-glandular-hairy, otherwise glabrous or moderately unicellular-hairy. Flowers opening before or with leaves, erect to horizontal, very fragrant; calyx lobes 0.1-3 mm, scattered eglandular-hairy and/or stipitate-glandular-hairy, otherwise sparsely to moderately unicellular-hairy, margins eglandular-hairy; corolla white, sometimes pink-tinged, with contrasting yellow blotch on upper lobe, funnelform, 25-42 mm, scattered stipitate-glandular-hairy (hairs often continuing in lines up lobes), otherwise sparsely to moderately unicellular-hairy on outer surface, petals connate, lobes 9-21 mm, tube usually ± gradually expanded into lobes, 15-31 mm (longer than lobes); stamens 5, much exserted, ± unequal, 37-69 mm. Capsules borne on erect pedicels, 14-22 × 3-4 mm, sparsely to moderately multicellular eglandular-hairy, otherwise moderately to densely unicellular-hairy. Seeds without distinct tails; testa expanded, dorsiventrally flattened, ± loose. 2n = 26.
Flowering spring. Open, dry woodlands, rocky slopes; 0-500 m; Ala., Fla., Ga., Miss., Tenn.
Rhododendron alabamense may be most closely related to a clade containing orange-red-flowered species (K. A. Kron 1993). This species has sometimes been confused with R. eastmanii; R. alabamense flowers before or as the leaves expand whereas R. eastmanii flowers after the leaves have expanded. Hybrids with R. canescens are known.