Rhododendron viscosum is a shrub 1-2 m tall, colonial from root sprouts; roots associated with highly specialized ascomycota ericoid mycorrhizae, (Allen1991); twigs slender, hairy when young, spiraled at ends of erect branches, like upward-facing umbrella ribs, winter flower buds large, pale greenish.
Leaves alternate, to 6 cm, widest above middle, often tightly spiraled at ends of twigs, hairy, tip with a short point.
Flowers white, spicy-fragrant, irregular, to 4 cm long, sticky-hairy, in small clusters at ends of twigs; blooms after leafing out, June-July.
Fruit dry capsules, splitting open to release very small seeds, wind dispersed in winter.
Wetland status: OBL.
Frequency in NYC: Occasional. listed as exploitably vulnerable in NYS (USDA, NRCS 2010).
Habitat: Shade tolerant, but may not bloom in deep shade. Soil pH 4-7 (USDA, NRCS 2010). Tolerant of saturated soil for up to 75% of growing season; Tolerant of shade, soil compaction. Moderately tolerant of drought. Intolerant of salt (Hightshoe 1988).
Notes: Twigs and buds eaten by rabbits and deer (Martin et al 1951).