14 THE FRUIT GROWER'S GUIDE. 



will be referred to also firmer soil, with moisture near the surface, are the correctives or 

 preventives, in inciting a network composed of multitudinous fibrous roots (<?, p. 13); 

 these are the natural producers of sturdy, short-jointed, fruitful wood. If the growth 

 of a tree is not so free as is desirable, the soil must be enriched, and if dry made moist, 

 and kept so by judicious mulchings, to sustain healthy growth, as will be explained. 

 Shortening the branches of trees has also a direct tendency to promote vigorous growth. 

 When the growth of a tree is too exuberant, then the roots, not the branches, must be 

 shortened ; or, in other words, branch pruning increases vigour in growth, while root 

 pruning subdues it. 



For affording practical guidance, it is scarcely necessary to enlarge on the composition 

 and character of the stems of trees. Obviously, they serve the all-important purpose 

 of conveying sap which the roots abstract from the earth for the support of themselves, 

 their leaves, and fruit. These stems are protected with a covering, which is analogous 

 to the skins of animals, and known as bark. It is smooth in young shoots, rugged, in con- 

 sequence of an aggregation of layers, on the older parts. It is protective in its nature and 

 absorbent. It aids in the maintenance of an equability of temperature, and a consequent 

 uniformity in the fluidity of the sap. Beneath the outer is the inner bark, or liber, under 

 which the sap mainly, but not exclusively, flows, and in the process of grafting, as will be 

 explained, the inner bark of the two parts to be united must be in juxtaposition for the 

 free transit of sap from one to the other, as it does not pass upwards through the outer 

 layer, which is often a mere incrustation of inert matter. Yet moisture passes through 

 it, or trees would not be injured or killed by a thick coating of gas tar, or other dangerous 

 application to protect them from animals or insects. It is also known that by encasing 

 the stems of newly-planted trees of large size, and keeping the bandages moist, the 

 growth of the trees is assisted materially. As has been previously suggested, the bark 

 should be kept clean, as it can be, by applications that will be mentioned, which are 

 not injurious: but the plan, not yet obsolete, of scraping all the bark that can be 

 removed from trees and vines, is, for the reasons above indicated, little short of barbarous, 

 and should forthwith cease. 



LEAVES. 



Passing to the leaves of trees, we are brought into contact with organs of the 

 utmost importance, and their nature and functions should be understood by all growers 

 of fruit. The leaves of trees may be said to constitute both the lungs and laboratory of 



