THE ECOLOGY OF THE UPPEK GANGETIC PLAIN. 307 



nial grasses are destroyed, and the ground left practically bare 

 (Fig. 14). 



In consequence of the severe grazing there is no cover of vegeta- 

 tion on the ground to aid in conservation of the monsoon rains. 

 Where drainage has been established, runoff of the monsoon rainfall 

 is very rapid and complete ; where the land is flat, the vegetation has 

 no effect in preventing runoff. 



The scattering thorny shrubs and small trees, with a few inedible 

 exceptions, are kept eaten done to small dense rounded bushes wher- 

 ever and as long as animals are able to reach them. 



Gutting for food and fuel. In India a very large proportion 

 of the plants comprising the flora is made use of by man for 

 some specific purpose, especially for food and medicines. Perhaps the 

 results of all such exploitation are not in the longrun very detrimental. 

 Usually it is parts that are not essential to the life of the plant that are 

 used for food. It is for forage and fuel that man works the greatest 

 havoc with the vegetation. Throughout the year, and especially during 

 the hot season, much of the available grass covering is cut off just 

 below the surface of the soil for fodder for domestic animals. It is 

 only the most persistent perennials that can survive such treatment. 

 In the Upper Gangetic Plain no natural fuel remains except a few 

 species of xerophytic shrubs and small tres3, and in most places 

 these are periodically cut, sometimes almost to the extinction point. 

 The fine groves about villages are all planted, and these alone escape 

 the unremitting struggle of man to find fuel. There is no attempt 

 locally at conservation of plant resources. 



Wild fires are negligible as a factor influencing vegetation, for 

 the reason that the land is so intensively cultivated and grazed that 

 there is nothing left to burn. 



Wild grazing animals are not numerous and are of little 

 importance. Earthworms are abundant during the rains, and their 

 burrows probably are of considerable importance in promoting 

 aeration and water penetration. Numerous species of black ants 

 probably render a similar service. In general, insect pests are 

 relatively unimportant. It is uncommon to find the indigenous 

 vegetation eaten to any great extent. 



White ants, White ants are the only insects that exert any 

 great influence on the vegetation. They are found everywhere and 

 are almost unbelievably abundant. Doubtless their burrows function 

 as do those of the black ants, and they reach a depth of 5 feet or 

 more. It is only rarely that white ants attack living plants, though 

 they closely follow dieing parts and keep them eaten away. When 

 grasses and other plants, especially the annual vegetation, die, the 



