no Bulletin 393 



The vigorous spurs seem to favor fruit setting because they can supply 

 the developing fruits with an abundance of water and food. Seeds appear 

 to be valuable because they supplement the forces that bring sap to the 

 fruit. vStrong seeds are of primary importance for the setting of fruit 

 on relatively weak spurs; they are of lesser importance for the setting 

 of fruit on strong spurs. 



The number of strong seeds is dependent on effective fertilization, 

 which in turn presupposes cross-pollination. Even tho the grower may 

 plant several varieties of the same fruit which bloom during the same 

 time, nevertheless cross-pollination is frequently prevented by unfavorable 

 weather during blooming time. Man has little control over the weather. 

 On the other hand, man may influence the vigor of the tree by cultural 

 methods. Trees in sod, for example, are usually less vigorous than trees 

 in a tilled orchard. The latter, as a rule, produce heavier crops of fruit. 



In Mr. Cornwall's orchard, at Pultneyville, New York, the Baldwin 

 trees were heavily laden with fruit in 191 5. Other Baldwin trees around 

 Pultneyville produced relatively light crops that year. The weather 

 at blooming time in that locality was cold, cloudy, windy, and rainy — 

 very unfavorable for cross-pollination. The trees on the Cornwall farm 

 were in the best of condition. The owner plowed his orchard very early 

 in the spring and put in a cover crop the latter part of June and early 

 in July. This treatment would be conducive to rapid, vigorous growth 

 of the spurs early in spring, and early planting of the cover crop would 

 tend to check further elongation and permit of abundant food storage 

 in and near the terminal buds. According to the observ^ations recorded 

 herein, such conditions would favor fruit setting without the aid of many 

 strong seeds, and hence a fairly good crop might be expected even tho the 

 weather during blooming time were unfavorable. Plowing in late fall 

 under some conditions may prove more advantageous than ver>' late 

 spring plowing, so far as setting of fruit is concerned. 



The application of a quick-acting nitrogenous fertilizer, such as sodium 

 nitrate, early in spring may have a decided effect in stimulating early 

 and rapid spur growth that would be likely to set fruit the following 

 year. Some evidence for this suggestion is contained in the paper by 

 Lewis and Allen (191 5), received by the writer while the present reporl 

 was in the course of preparation. 



Much has been said regarding so-called self -sterility of certain varieticj 

 which under a given set of conditions seem to be benefited by cross- 

 pollination. As has been observed by Waite (1894) and others, th< 

 degree of self-sterility varies from year to year and in different tree? 

 of the same variety under different cultural treatments and in differeiH 

 localities. From the standjioint of the species, a condition of self-sterilit) 



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