The Corbett Tiger Reserve is a roughly trapezoid valley in
South Patlidoon below the central Himalayan foothills, with its long axis
more or less west to east; the western two thirds of the area is in the
Pauri Garhwal district of Uttranchal and the eastern one third in the
A hill ridge runs right through the long axis of the valley, centrally, and there are many lesser ridges that are also high though not even half as long; the highest of them all is Kanda Peak to the north west of the reserve, and the lowest elevation of the bed of the valley is about 400m.
The feature of this slightly elevated and ridged valley is the river Ramganga coursing through it, breaking into many subsidiary streams running in all directions to cut up the sandy, Shingly Valley bed into innumerable little ridges and ravines, and to form many islands. Here stands of Sheesham (Dalbergia Sissoo) cover the ground; for this reason they were called 'Sheesham Islands'. The course of the Ramganga through the reserve is sinuous; it enters the reserve on its northeast, near Gairal forest rest house, runs southwest again to emerge near Kalagarh. Most of the 'Sheesham Islands' are now submerged by the water spread of the Ramganga Project.
The Ramganga is practically the only perennial source of
water to the valley. During the height of summer, the innumerable streams
and Nullahs dry up, except in places, to form stagnant pools; the water
spread of the reservoir extending into the reserve also holds water, but
not running water. Malani Tal in Malani holds water right through the
The ridges are forested, their vegetation varying considerably; there are also valley bed tree forests and pastures, and in and around the water spread aquatic and waterside plants are still in the process of establishing themselves.
There are three well-differentiated seasons - Winter from
November to February, summer from March to June, and the rainy season from
July to late October. Winter nights are very cold, and there is frost and
a freezing log in the low-lying areas; the days are cool, averaging about
25°C- the night's average 40°C. June is the hottest month and is
summer the day temperature may go as high as 44°C, but the night's
average only 22°C. In Summer, pre-Monsoon storms and hailstorms are
not uncommon, but seldom severe.
Rainfall varies widely, from about 1,400 mm in the outer hills to 2,800 mm in the upper hills; the main Ramganga valley receives an average of 1,550mm. The bulk of the rains is during the South West Monsoon, from July to October. The place also gets some rainfall during the winter months, from December to the end of February. Humidity is high during the rainy and winter seasons and never low even in summer.
Sal And Its Associates
The reserve is especially notable for its Sal (Shorea Robusta), one of the major construction timbers of the country. Sal grows gregariously, along with a few so-called 'Sal Associates', and magnificent stands of almost pure Sal are to be found both in the hill ridges and in the flat valley.
Sal predominates in the tree forests, and among its familiar 'associates' here may be mentioned the 'Rohini' (Mallotus Philippinesis) for which wild Elephants seem to have a penchant, and the Karipak ('Jalneem' locally) to supply the entire requirement of all the kitchens in the south, and it is unknown to the culinary culture of Uttar Pradesh! The 'Mota Sal' stand at Dhikala is especially notable, with the trees of robust girth towering some 33m in the south.
Mixed Dry Deciduous Trees
There are mixed Dry Deciduous Forests on the 'Bhabar' flats, featuring such trees as the 'Ber' (Zizyphus mauritians), 'Kurha' (Holarrhena Antidysenterica), 'Bael' (Aegle Marmelos), 'Dhak' (Butea Monosperma), and occasional Simal (Bombax Ceiba), 'Jhingan' (Lannea Coromandelica) and 'Khair' (Acacia Catechu): prominent in the undershrub are Marorphali (Helicteres Isora), species of Grewia and Rohini (Mallouts Philippinesis).
The forests on the rugged Shiwalik (also spelt as Siwalik) sand rocks occur mostly to the south of the reserve and contain a sprinkling of Sal, but the main species of these mixed forests are: Bakli (Anogeissus Latifolia), Khair (Acacia Catechu), Jhingan (Lannea Coromandelica), Tendu (Diospyros Tomentosa), Pula (Kydia Calycina) and Sain (Terminalia Tomentosa) with the Chir Pine in places.
Good stands of Sal occur in the flat country, in the Shiwalik conglomerate forests. Along the Ramganga are stands of 'Sheesham', mostly of young trees, and occasionally lone 'Simal' (Bombax Ceiba) trees.
The 'Chuars' constitute an important and characteristic part of the reserve, providing most of the grazing to the herbivores. A 'Chaur' is a flat grassy black, sometimes quite extensive, and the important 'Chuars' are at Dhikala (Partly inundated now), Phulai, Khinanauli, Paterpani, Mohanpani, Bhadhai and Bijrani. These are generally man made being the reversion of abandoned cultivation to wildness, and carry many herbs and both tall and short grasses, and provide fodder to herbivores from Hog Deer to Elephants, and in places cover for the predators.
The Nullahs and ravines that go deep into the tree forests are of no less importance to the animals. These hold brakes of Bamboo along their margins and also of thick shrub growth, useful both as fodder and as cover. The thick brakes of a succulent plant, Ardisia Solanacea (and A. Floribunda), provide all herbivores with a source of life giving water during the driest months.