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INTRODUCTION 
ASPECTS OF THE VEGETATION OF SIMLA 
From Dr. T. Thomson’s 4 Western Himalaya and Tibet ’ the 
following observations, made in 1847-1848, are extracted : — 
In consequence of the sudden elevation of the mountain 
range at the place where Simla has been built, there is a most 
complete and surprising change in the vegetation and general 
appearance of the scenery. During the last ascent on the road 
from the plains this is sufficiently perceptible, although from the 
great ravages which the proximity of so large a population has 
made in the oak woods, only a few stunted bushes are now 
left on the southern exposure. Between the plains and Simla the 
hills are totally devoid of trees, but immediately on gaining the 
top of the ridge on which the station is built, we enter a fine 
forest, which covers all the broader parts of the range, especially 
the slopes which have a northern aspect. 
The nature of the forest varies a good deal with the exposure 
and with the quality of the soil. By far the greater part consists 
of an oak [ Quercus incana ] and a rhododendron [ Rhododendron 
arbor eum], both small evergreen trees, rarely exceeding thirty or 
forty feet, with wide-spreading arms and rugged twisted branches. 
A species of Andromeda [Pieris ovalifolia ] is also very common, 
and a holly [ Ilex dipyrena ], Euonymus, Ehamnus, and Benthamia 
\Cornus\ are the other more common trees, if we except the 
Goniferce, of which four species occur. Of these Pinus longifolia 
is common at the western or lower extremity of the station, and 
prevails, to the exclusion of any other tree, on the dry sunny 
spurs which run towards the south, at elevations from 2,000 to 
5.000 ft. This species is, of all the Indian pines known to me, 
except its near ally P. Khasyana, that which is capable of endur- 
ing the most heat, and at the same time the greatest variation in 
amount of moisture, as it is found at elevations of not more than 
1.000 feet above the level of the sea, equally in the hot humid 
valleys of Sikkim, where it enjoys a perpetual vapour-bath, and 
on the dry sandstone hills of the Upper Punjab, on which rain 
hardly ever falls. It is only, however, at low elevations, where 
the mean temperature is high, that it is capable of supporting a 
great amount of humidity, for in the damp climates of the Himalaya 
it is entirely wanting, except in the deepest valleys ; and even in 
the drier districts it is always observed to select the sunnier, and 
therefore warmer exposures. Its upper limit is usually about 
7.000 feet above the level of the sea, though on Jako at Simla a 
few stunted trees rise as high as 7,700 feet. 
