19 1 a] Winter Washing of Fruit Trees. 835 



orchards, moreover, nitrification probably proceeds more 

 rapidly than in those on grass land. Hence, in the latter, 

 nitrogen in the form of nitrate of soda or sulphate of ammonia 

 seems preferable to organic nitrogen ; whereas organic 

 manures may be of equal value for cultivated soil. Where 

 nitrate of soda is used, it should be applied in the spring. 



As a potassic manure, sulphate or chloride of potash may 

 be recommended; the latter should only be used on soils 

 rich in lime. Kainit is considered by some authorities to be 

 unsuitable for fruit. 



Phosphoric acid is generally best supplied in the form of 

 basic slag, except where immediate effect is required, in which 

 case superphosphate should be used, and supplemented latet 

 with slag. 



Lime may be applied as quicklime, slaked lime or chalk, 

 the last being safer if it is likely to be brought at once into 

 contact with the delicate rootlets. As a surface-dressing the 

 other two are perfectly safe. 



Lime, phosphoric acid, and potash may be applied in 

 autumn, winter or spring. In cultivated soil the manures 

 may be applied as a surface-dressing and then worked into 

 the ground, but in grass orchards this method is slow in pro- 

 ducing effect. To produce quicker results a series of small 

 holes may be drilled in the ground in the neighbourhood of 

 the young roots, or strips of turf may be temporarily removed 

 in the same region, and the manure incorporated directly 

 with the soil. The quantity of manure required should be 

 varied according to the size of the tree. Since in the case of 

 trees some time is required for the manure to make its effect 

 visible, it should not be concluded that the application has 

 had no result if no response is apparent during the first 

 season . 



Stock should be regularly turned into the orchards for graz- 

 ing, since they are able to supply considerable quantities of 

 nitrogen as manure. The practice of turning in pigs during 

 the winter is useful, for they not only improve the soil by the 

 addition of manure, but by bringing about its aeration by 

 constant grubbing, while they also destroy many larvas and 

 pupae of insects. 



Pruning. — If a young standard tree is properly pruned for 



