Tree Rhododendron

Description:

Its name means "tending to be woody or growing in a tree-like form". It has been recorded as reaching heights of up to 20 m, although more usually it has a height and spread up to 12 m (36 ft) x 12 m (36 ft).

Habitat:

Found in Bhutan, China, India, Nepal, Sri Lanka and Thailand. Rhododendron arboreum (Laligurans) is also the national flower of Nepal. It prefers moist but well-drained, leafy, humus-rich, acid soil, in dappled shade

Notes:

I spotted this on a short nature trail near the top of the summit of Doi Inthanon in the national park of the same name.