NECESSITY FOU DRAINAGE. 93 



eight feet below the surface in soils that were naturally 

 drained and not retentive of water. Although it is a 

 matter of conjecture if the roots would descend so far 

 when ample moisture may be found near the surface, the 

 reasonable probability is that they would not. If the 

 habit of deep growth should be a fixed one, it would be 

 a question as to how deep the drains should be made in 

 soils that are well supplied with plant-food in the subsoil, 

 but were too retentive of water to permit a healthy growth 

 at considerable depth. It is evident that with irrigation, 

 and sufficiently deep drainage combined, the vine and 

 fruit grower can render himself largely independent of 

 seasons and locality, and give his vines and trees an ample 

 depth of soil in which to spread their roots, and at the 

 same time furnish them with all the moisture they may 

 need near the surface. The practice will necessarily be 

 modified by the character of the soil and situation ; fruit 

 growers, however, are rarely deficient in intelligence, skill, 

 or patience, and are abundantly able to make such modi- 

 fications of the general principles given in this work as 

 may be needed. The practice in those countries where 

 orchards and vineyards are irrigated is as follows: The 

 periods of irrigation depend upon the heat of* the season 

 and the dryness of the soil. In the north of France and 

 parts of Germany, water is given without any regularity, 

 and only when the exceptional circumstances of the sea- 

 son make it needful. But further south, where the sum- 

 mers are hot and dry, and periodical drouths occur, fruit 

 trees are irrigated constantly and vines periodically. The 

 penalty for an excessive irrigation is a crop of fruit of in- 

 ferior quality; watery, soft, and without flavor; the wood 

 and leaf are pushed at the expense of the fruit ; succulent 

 fruits crack and burst, and shelled fruits have soft and 

 imperfect husks. The effect of too copious irrigation 

 upon nut-bearing trees is to develop the whole fruit 

 simultaneously, the inner portions complete its growth 



