4 io SCIENCE PROGRESS 



the effect of manuring was very considerable, showing that the 

 method of experimentation was not in fault : the influence of 

 the treatment on the growth and fruiting of the trees began to 

 be appreciable after the first or second season and has become 

 more marked as time went on : thus in the seventh year after 

 planting the value of the crops from the trees receiving a 

 deficiency of manure was 40 per cent, below the normal and 

 that from those receiving extra manure was 30 per cent, above 

 the normal. 



Whether or not manures will eventually have an effect on 

 the trees at the Fruit Farm is a matter of conjecture ; it is 

 certain that they have been quite unaffected by all that has 

 been applied to them during the past seventeen years. No 

 sweeping conclusion can, of course, be drawn from this that 

 such trees should never be manured; but inasmuch as our field 

 does not appear to be exceptional, it seems certain that trees 

 would frequently exhibit a similar behaviour elsewhere and 

 that a grower would be wise before spending money in manure 

 to make sure, either by experiments on a small scale or by 

 considering the results obtained by his neighbours, whether 

 that manure is likely to be beneficial in his own case ; otherwise, 

 as with us, all his expenditure in dressing his land will be wasted. 



Whilst manures have been thus ineffective on apple trees, 

 it is remarkable that, in this same soil, they have proved to be 

 absolutely essential to bush fruits. Thus with gooseberries, 

 plots containing four plants of each of forty-five different 

 varieties have received continuously different dressings. During 

 the first five years the crops from those receiving dung were 

 35 per cent, greater than those receiving no manure and the 

 superiority in the size of the fruits was very marked ; but 

 artificial manures had very little effect, at any rate, on the 

 cropping, the average yield from plots so treated being only 

 1 per cent, above that from the unmanured plots. These 

 experiments have been continued for fifteen years and the plots 

 now are even more striking than they were at first ; for whilst 

 those which have received dung have 37 per cent, of the original 

 bushes planted in them still alive, the unmanured plots have 

 only 9 per cent, and those receiving artificials 23 per cent. The 

 fruit is now quite valueless except from the bushes receiving 

 dung. 



The effect of varying the amount of the dressings was 



