290 



FUNDAMENTALS OF FRUIT PRODUCTION 



Chandler. In one case, at Brandsville, Mar. 16, 1911, unfertilized trees 

 lost 98.4 per cent, of their buds while trees fertilized with ammonium 

 sulfate lost 77.6 per cent, and those which had received nitrate of soda 

 lost 87.1 per cent. In one instance the fertilizer saved enough buds to 

 make a full crop, in the other enough for a fair crop. 



Late cultivation has been reported to have the same results in 

 retarding the rest period and increasing hardiness. 



Thinning. — Thinning has been observed to have beneficial effects 

 on hardiness. Chandler^^ cites a case in which buds of certain varieties 

 survived a winter that killed those of most varieties. These trees then 

 bore a full crop but in the following winter their fruit buds succumbed 

 while the varieties tender in the previous year survived. To secure 

 experimental data the fruit on half of each of several heavily loaded trees 

 was thinned with the results shown in Table 31. When the experiment 



Table 31. — Effect of Thinning Fkuit on Hardiness of Buds'^ 



was repeated in 1908,''* the effects of the freeze of Jan. 12, 1909, following 

 weather such that all buds may be regarded as dormant at the time, were 

 quite different, the unthinned limbs losing 92.5 and the thinned 93.2 

 per cent, of their buds. Laboratory results are reported as follows: 

 "These results suggest that thinning has its effect on the rest period 

 rather than on the intrinsic hardiness of the buds. Where the tree is 

 bent under a heavy load and under the strain of bearing a heavy crop, 

 as when it is not thinned, the moisture supply probably being partially 

 shut off, the same condition will prevail, at least to some extent, as when 

 the trees are not cultivated; they will become dormant earlier and end 

 their rest period earlier. Thus thinning, like heavy pruning and ferti- 

 lizing with nitrogen can be expected to increase the hardiness of peach 

 fruit buds only in climates like that from Central Missouri South, where 

 there is likely to be weather warm enough to start the buds into growth 

 before the effect of the rest period ends." 



