Fl. U.S. 425 (1824)
Verified by:
Shrub or small tree to 6m tall, usually non-rhizomatous; young twigs yellow-brown or rarely red-brown, glabrous or rarely very sparsely covered with unicellular hairs. Vegetative bud scales glabrous abaxially; margin unicellular-ciliate. Leaf blade membranaceous, ovate or obovate to elliptic, (4.5-)4.8-7.8(-10.5) x (1.6-) 1.9-2.6(-3.0)cm; base acute to oblique; apex acute to obtuse, often mucronate; adaxial surface glabrous, the midvein sparsely to densely covered with unicellular hairs; abaxial surface glabrous, sometimes also glaucous, the midvein sparsely covered with multicellular eglandular hairs, occasionally glabrous; margin entire, ciliate with multicellular eglandular hairs; petiole (0.2-)0.4-0.9(-1.6)cm long; glabrous or sparsely covered with multicellular eglandular hairs. Flower bud scales chestnut brown; abaxial surface glabrous or rarely with very sparse unicellular hairs; margin unicellular ciliate. Flowers appearing with the leaves or after they have expanded; Inflorescence a shortened raceme of 3 to 7 flowers. Pedicels (0.6-)1.0-1.6 (-2.1)cm long, sparsely to densely covered with unicellular and multicellular gland-tipped hairs, occasionally only with multicellular eglandular or gland-tipped hairs, rarely glabrous. Sepals less than 0.1-0.5(-0.8)cm long, often varying in length on the same flower; margins glandular-fim-briate and setose or only glandular-fimbriate, rarely only setose; abaxial surface glabrous to sparsely covered with multicellular gland-tipped hairs, eglandular hairs or with both, rarely additionally covered with unicellular hairs. Corolla white, fragrance sweet, with a cinnamon quality, the tube longer than the limb and gradually expanding into it; upper corolla lobe (1.0-)1.3-1.9(-2.1) x (0.7-)0.9-1.4(-1.8)cm; lateral lobes (1.2-) 1.4-2.0(-2.4) x (0.5-)0.6-0.9 (-1.2)cm; corolla tube (2.0-)2.3-2.9(-3.3)cm long, 0.2-0.5(-0.6)cm wide at base; outer surface of corolla sparsely covered with unicellular hairs and multicellular gland-tipped hairs that continue in lines up the corolla lobes; inner surface of corolla sparsely to densely covered with unicellular hairs. Stamens (4.4-)5.3-6.9(-8.2)cm long, with dense terete or flattened unicellular hairs on proximal (2.7-)3.0-3.8(-4.5)cm of filament, exserted (2.3-)2.9-4.3(-5.0)cm beyond throat of corolla. Style (5.3-)5.6-6.9(-7.5)cm long, exserted (3.2-)3.6-4J(-5.4)cm beyond throat of corolla, with dense unicellular hairs on proximal (0.0-)0.2-1.4(-2.6)cm; stigma 0.1-0.3cm wide. Ovary (0.2-)03-0.4cm long, 0.1-0.3cm wide at the base, densely covered with multicellular glaAd-tipped hairs and unicellular hairs. Capsules (1.1ó)1.2ó1.7 x 0.5-0.8cm, ovate, sparsely covered with unicellular hairs and moderately covered with multicellular gland-tipped hairs. S eeds pale to dark chestnut brown, ovate or elHptic to fusiform, (0.8-)l.l-1.6(-2.0) x (0.4-)0.6-1.0 (-l.l)mm,tody(0.7-)0.8-1.8 of the seed, the cells short with transverse end-walls orisodlametric.
USA: West Virginia to Tennessee, North Carolina, Georgia and adjacent Alabama.
Along mountain streams, shrub balds and moist woods.
Azalea viscosa Marshall, Arbust. Amer. 15 (1785) non L. Type: n.v. Azalea arborescens Pursh, Fl. Am. Septentr. 152 (1814). Type: n.v. Azalea fragrans Raf., Ann. Nat. 12 (1820). Type: n.v. Rhododendron arborescens (Pursh) Torr. var. richardsonii Rehder, Monogr. Azaleas 168ó 169 (1921). Azalea arborescens Pursh var. richardsonii (Rehder) Ashe, J. Elisha Mitchell Sci. Soc. 38: 91 (1922). Type: North Carolina, Macon Co.: on Wayoh [sic] Bald, alt. 5200 ft, T G. Harbison 170 (holo. A).
Kron, K.A. (1993) A Revision of Rhododendron Section Pentanthera. Edinburgh Journal of Botany 50(3):287