Rhododendron macabeanum Balf.f.

Tree-like to 6 m tall. Leaves about 30 cm long. Flowers deep yellow with a purplish basal spot, produced after about 8 years from seed (earlier than other broad-leaf rhododendrons).

NE India

 

R. falconeri Hook. f. is similar but with paler flowers while R. magnificum Ward has flowers that vary from pale to deep rose or reddish purple and are more tubular bell-shaped.

Source: Davidson, B.; Craven, L.; Malone, B.; Davidson, R.; Wilson, J, ; Spencer, R. (1997). Rhododendron. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.

kingdom Plantae
phylum   Tracheophyta
class    Magnoliopsida
superorder     Asteranae
order      Ericales
family       Ericaceae
genus        Rhododendron L.