238 



POMOLOGY 



It is, of course, well known that a given variety or species 

 becomes somewhat adapted to the length of growing sea- 

 son in widely differing sections of the country, but this is 

 not to be interpreted as meaning that a variety of peach, 

 apple, or other fruit having the capacity to withstand a cer- 

 tain minimum degree of temperature may be acclimated to a 

 still lower one by adaptation. The work of Whitten, Dorsey, 

 Macoun, and others show adaptation within certain limits. 



208. Temperatures which injure setting of fruits. — It is 

 well known, as stated above, that frosts destroy fruit blos- 

 soms frequently, but it is also true that injury may occur 

 without apparently killing the tender tissues. The after 

 effects of the latter are seen in the heavy fall of fruit during 

 about three weeks following the blossom period. 



The following figures give the temperatures at which the 

 various fruits may be injured at blossom time: 



' See West, Frank L., and N. E. Edlefsen. Freezing of fruit buds. 

 Jour. Agr. Res., Vol. 20, No. 8. 1921. 



