I had gone to ‘Chandranahan’, a lake perched at 4050 metres in Rohru division of Shimla district and forming origin of river ‘Pabbar’. The trek of about 24 kms from Tangnu, the nearest road head, involved passing through beautiful Birch-Brown Oak-Himalayan Fir (Betula utilis-Quercus semecarpifolia-Abies spectabilis) forests forming timber line and merging into alpine meadows through a very narrow band of sub-alpine shrubs. Camping in alpine meadows has its own charm. I returned from this wonderful trek only yesterday. 
That this year we received less than normal rains was apparent from the near dry lake and almost parched vegetation enroute. We however, were blessed to observe good populations of Saussurea obvalata and Aconitum violaceum along the path. Shall share photographs of the trek soon. 

Will be looking for wonderful photgraphs from you