88 ON THE DISTRIBUTION OF FORESTS IN INDIA. 



XI. On the Distribution of Forests in India. By Dietrich 

 Brandis, Ph.D., Inspector- General of Forests, Calcutta. 



(Willi a i\iap./ f'lii-s pnper is reprinted from ■' Ocean Highways," Oct. 1872. 



In all countries the character of forest vegetation mainly depends 

 on soil, climate, and the action of man. In India the greater or less 

 degree of moisture is perhaps the most important element in this 

 respect. Moisture and rainfall are not identical terms. Dew and 

 the aqueous vapour, dissolved in the atmosphere, or the water 

 derived from the overflow of rivers and from percolation, are sources 

 of moisture as important for the maintenance of arborescent vegeta- 

 tion as the fall of rain and snow. It would greatly facilitate the 

 labours of the forester, and of the botanist who inquires after the 

 geographical distribution of forest trees, if the amount of atmospheric 

 moisture and the formation of dew during the seasons of the year in 

 different parts of India had been sufficiently studied; hut, in the 

 present state of our knowledge, we must be satisfied with dividing 

 India into regions and zones according to the more or less heavy 

 rainfall during the year. The arid region, with a normal annual 

 rainfall of less than fifteen inches, occupies a large proportion of the 

 north-west corner of India, from the Salt range in the north, to the 

 mouths of the Indus in the south, and from the Suleiman range in 

 the west to the Aravulli Hills in the east. It includes the southern 

 portion of the Punjab, the province of Sindh, the States of Bhawul- 

 poor, Ivairpoor, Bikanir, Jessulmir, and the greater part of Marwar. 

 Throughout this vast region, which covers an area equal to that of 

 the kingdom of Prussia, with a population of about twelve millions, 

 the rains are not only scanty but most uncertain. It is not a rare 

 occurrence for several years to pass in succession without any 

 showers, and then there is a heavy downpour, generally in winter, 

 and occasionally in August or September. There are, however, no 

 regular winter or summer rains. A scanty, thorny scrub on the hills 

 gives ample employment to the botanist, for it is here that the repre- 

 sentatives of the Arabian and Persian flora mingle with the vegeta- 

 tion which is peculiar to India; but the work of the forester is 

 mainly confined to the belts of low country along the Indus and its 

 great branches. In Sindh, for instance, the area of forest land at 

 the disposal of the State covers 350,000 acres, all situated on the 

 fertile alluvial soil on both banks of the Indus, some of which is 

 inundated annually by the summer floods of this large river, the 

 remainder being moistened by percolation. In lower and middle 



