Yields 341 



best practice. Thinning and fertilization are much 

 neglected and this accounts for many of the low yielding 

 orchards. Eesults are not secured by performing one 

 orchard operation thoroughly and neglecting another. 

 Proper pruning, spraying, thinning and an abundance of 

 available plant-food should insure large commercial crops 

 under normal conditions. 



In studying yield, one should consider not only the per- 

 formances of individual trees or orchards in a given region, 

 but more particularly the average yield on well managed 

 orchards typical of the region. Soil fertility and good 

 orchard management do not entirely determine yields. 

 Unfavorable weather at blooming time occurs more fre- 

 quently in some regions than in others and very often 

 greatly reduces annual yields. There are certain areas, 

 particularly in the more mountainous parts of the country, 

 where on the average one crop out of every four or five 

 is wiped out or severely damaged by hail. It is easy to 

 understand how the profits of good crop years may be 

 almost wiped out by total failures in other years. 



In the Wenatchee district of the Northwest, a total fruit 

 crop failure is unknown, while in regions like the Ozarks, 

 the Ohio Valley and the Missouri River region, Michigan 

 and in fact most eastern sections, very light crops and 

 even failures are not infrequent. Most of these failures 

 are due to frost damage, or to unfavorable weather at 

 blooming time which prevents pollination. The frequency 

 of light crops and failures is exceedingly important. 



For a period of ten years, the Northwest has had an 

 average of nearly 80 per cent of a full apple crop, while 

 for the same period Missouri, Illinois and the middle 

 western states have had scarcely 50 per cent of an apple 



