Rhododendron wightii Hook. f., Rhododendron Sikkim Himalaya 3: , pl. 27 1851. ;

Common name: Wight’s Rhododendron
S-Tibet, Bhutan, Nepal, Assam, Sikkim as per Catalogue of Life;

Shrub 2-5m; branchlets glabrous or puberulous. Leaves broadly elliptic or obovate, 9-15×4-6cm, rounded or acute, base rounded or somewhat cuneate, densely appressed reddish brown tomentose beneath with compound hairs; petioles 1-2cm, stout, closely greyish floccose above. Racemes loose, 12-20 pundulous flowers; pedicels 1.5-2.5m, tomentose. Calyx minute, 5-lobed. Corolla campanulate or broadly campanulate, 3-3.5cm, mostly 5-lobed, pale or lemon-yellow with reddish or brownish spots. 3-3.5cm, mostly 5-lobed, pale or lemon-yellow with reddish or brownish spots. Stamens 10;filaments pubescent at base. Ovary brown tomentose; style glabrous. Capsules curved, 2.5-4×0.5-0.7cm.
Fir forests and Juniper/Rhododendron scrub
(Attributions- Grierson A.J.C&Long D.G. Flora of Bhutan. Volume 2 part 1. Published by RBGE 1991 from Bhutan Biodiversity Portal)



white Rhododendrones : Attachments (2). 2 posts by 2 authors.

These were found on lower heights.
I have seen Rhododendrones in all the colours but very few white ones, They were trees of medium height

One possibility is Rhododendron wightii 
One feature of this is that leaves are brownish of greyish on the underside.



2 more Rhododendrons : Mixed thread- 1 correct image as above. 3 posts by 2 authors.
Two more Rhododendrons- Perhaps
100_1255.JPG- R. pronum
100_1263.JPG- R. hirsutum
on way to Bumla pass- 11000-12000 ft. Needs confirmation

The pink flowered rhododendron is R.campanulatum and the first one looks like R. anthopogon (note:-flowers should be in yellow color) and if not than check R.lepidotum

Please find attached herewith the identified species. R. wightii & R. campanulatum respectively.