PURE versus MIXED CROPS. 113 



and the roots of which are stronger and better ramified, affords 

 very great protection to the former against damage by snow and 

 wind. Then, again, as insects often attack only sickly trees (which 

 are relatively not numerous in mixed forests), and not unfrequently 

 confine their depredations, when they do attack healthy individuals 

 as well, to a single or only a few species, their ravages are natur- 

 ally not so extensive in mixed as in pure forest. And if the forests 

 in question contain conifers, the companionship of broad-leaved 

 trees is specially beneficial in that the numbers of the natural 

 enemies of insects (birds, rodents, &c.) are generally increased by 

 their presence. Again species, which in early youth are delicate, 

 find much more protection against frost, drought, &c., in a mixed 

 than in a pure forest. Another beneficial effect of mixture is, that 

 it contributes very materially towards the diminution of diseases, 

 of which the attacks of fungi are either the symptom or direct 

 cause. Lastly, trees, the leaves of which are eaten by cattle or 

 deer, run less risk of being browsed down when they grow here 

 and there mixed with other species than when they all stand to- 

 gether as they do in pure forests. 



VIII. The relative suitability of the soil and locality for our 

 various species is most easily recognised when they are growing to- 

 gether, so that the forester has then no difficulty in ascertaining at 

 once, and with certainty, what species he should grow or favour in any 

 given soil or locality. This advantage is especially emphasized in a 

 new country like India, where so little is yet known of the habits 

 and requirements of even our principal species, and it becomes 

 most conspicuous when sowings or plantations on a large scale are 

 to be made. Mistakes committed in executing the various forest 

 operations can be detected much more easily in mixed than in pure 

 crops, and generally, if not always, early enough to prevent any 

 serious or further damage. 



IX. When a forest is regenerated naturally, its regeneration is 

 better assured if it is mixed. Seeds of one species or another are 

 sure to be produced in less or greater abundance every year all 

 over the forest. A great number of these must germinate, and, 

 whenever sufficient light reaches the ground and other conditions 

 are favourable, a large proportion of the seedlings thus produced 

 must establish themselves. Moreover, as the seeds of different 

 species germinate with different degrees of facility and require 

 different degrees of heat and soaking, it is certain that, whatever 

 the character of the season of vegetation may be, some seedlings 

 cannot fail to be produced every year. Thus in mixed forest re- 



