4 o8 SCIENCE PROGRESS 



root-pruning was more frequent the total weight of fruit was 

 quite insignificant. 



Evidently root-pruning is not an operation to be indulged 

 in except in extreme cases and then only sparingly, when, for 

 instance, a tree persists in making rampant growth and does 

 not flower. (The absence of fruit, be it noted, if the tree 

 has flowered, is not a case demanding root-pruning; it is 

 generally due to the flowers not having been properly 

 fertilised.) Root-pruning is rarely indulged in except in 

 private gardens ; in nine cases out of ten its practice there 

 is due to excessive branch-pruning. The effect of the latter is, 

 as has been seen, to reduce the fruiting, hence the necessity 

 of pruning the roots in order to restore the balance between 

 roots and branches. But it is not a very rational method of 

 treating a tree to injure it in one way and then injure it in 

 another to counterbalance the damage done. If there was less 

 branch-pruning we should hear very little about root-pruning. 

 In one general case only may it be inevitable, that of strong- 

 growing trees planted against a wall ; severe branch-pruning is 

 necessary, if the tree is to be confined to the wall and this will 

 entail a corresponding pruning of the roots. 



Manuring 



The most conspicuous features of the results obtained at 

 the Woburn Experimental Fruit Farm on the subject of the 

 manuring of fruit trees is the smallness of the effect produced 

 by any manures on apple and similar trees and the essential 

 difference between the requirements of these and of the smaller 

 fruits, such as gooseberries, currants and strawberries. Doubt- 

 less these results, as must be the case with all manurial 

 experiments, are largely dependent on the nature of the soil but 

 it must be borne in mind that the soil of the farm is by no means 

 of exceptional richness, as measured either by analysis or by 

 the behaviour of farm crops in it before it was converted into 

 a fruit farm. It was nothing more than agricultural land of 

 moderate fertility, which would probably be below the average 

 as a favourable soil for fruit growing ; the upper layer of good 

 soil is only about seven inches deep and below that there is a 

 very stiff clay subsoil, into which the roots of trees show a 

 great disinclination to penetrate and from which, therefore, they 



