528 plint's natural histoey. |_ Bo °k XVII. 



remedies as well. Some of these remedies may be applied to 

 all kinds of trees in common, while others, again, are peculiar 

 to some only. The methods that are common to them all, are, 

 baring the roots, or moulding them up, thus admitting the air 

 or keeping it away, as the case may be ; giving them water, or 

 depriving them of it, refreshing them with the nutritious juices 

 of manure, and lightening them of their burdens by pruning. 

 The operation, too, of bleeding, 35 as it were, is performed upon 

 them by withdrawing their juices, and the bark is scraped all 

 round 36 to improve them. In the vine, the stock branches are 

 sometimes lengthened out, and at other times repressed ; the 

 buds too are smoothed, and in a measure polished up, in case 

 the cold weather has made them rough and scaly. These re- 

 medies are better suited to some kinds of trees and less so to 

 others : thus the cypress, for instance, has a dislike to water, 

 and manifests an aversion to manure, spading round it, pruning, 

 and, indeed, remedial operations of every kind ; nay, what is 

 more, it is killed by irrigation, while, on the other hand, the 

 vine and the pomegranate receive their principal nutriment 

 from it. In the fig, again, the tree is nourished by watering, 

 while the very same thing will make the fruit pine and die : 

 the almond, too, if the ground is spaded about it, will lose its 

 blossom. In the same way, too, there must be no digging 

 about the roots of trees when newly grafted, or indeed until 

 such time as they are sufficiently strong to bear. Many 

 trees require that all superfluous burdens should be pruned 

 away from them, just as we ourselves cut the nails and hair. 

 Old trees are often cut down to the ground, and then shoot up 

 again from one of the suckers ; this, however, is not the case 

 with all of them, but only those, the nature of which, as we 

 have already stated, 37 will admit of it. 



CHAP. 40. METHODS OF IRRIGATION. 



Watering is good for trees during the heats of summer, but 

 injurious in winter ; the effects of it are of a varied nature in 

 autumn, and depend upon the peculiar nature of the soil. 

 Thus, in Spain for instance, the vintager gathers the grapes 

 while the ground beneath is under water ; on the other hand, 

 in most parts of the world, it is absolutely necessary to carry 

 off the autumn rains by draining. It is about the rising of the 



35 See c. 43 of this Book. 36 g ee c# 45 f t^g Book. 



37 In B. xvi. cc. 53, 56, 66 } 67, and 90. 



