IV 



WINTERKILLING 



In considering geographic and climatic factors we 

 must give some attention to another matter which is of 

 considerable importance in certain locahties. Winter- 

 kilHng has always been a large and interesting problem 

 with fruit growers in this country, but is of compara- 

 tively little importance in growing apples, especially 

 in the management of commercial orchards. In the 

 great apple-growing regions winterkilling is practi- 

 cally a negligible factor. In sections where winter- 

 killing is a serious danger apple growing can never 

 become an extensive industry. Since, however, every 

 householder in every civilized community in temper- 

 ate climates wishes to grow some apples, and since 

 winterkilling is a really serious matter in some of these 

 localities, it is necessary to consider this subject with 

 due care. 



Winterkilling is of three sorts: (i) The killing of 

 the buds; (2) the killing of the young growth; (3) 

 root killing. The killing of fruit buds, though a very 

 serious matter in peach growing and with some va- 

 rieties of plums, very seldom occurs with apples. Ap- 

 ple buds are well protected and hardy. Any variety 

 sufficiently hardy to carry its wood through the winter 

 will usually save its buds also. 



The young growth on apple trees sometimes kills in 

 severe winters. This damage is more likely to occur 

 on newly planted trees than on those well established. 

 It has been shown that this damage occurs largely 



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