9 8 



In the root system of. trees growing out of doors there is great 

 difference in the relative hardiness. The crown of the tree — that is, 

 the part of the root just beneath the ground — will withstand con- 

 siderably lower temperatures than parts of the root lower down, and 

 the small ends of the roots kill more easily than the larger parts. 

 In fact as the roots extend away from the crown they become more 

 and more tender and apparently this tenderness is greater on those 

 roots that extend downward into the soil. Goff thinks that in' 

 Wisconsin the ends of the roots may be killed during every winter. 

 The following table presents data covering this point. The Angers 

 quince roots were frozen on January 25, 1913; the seedling peach 

 roots on March 22, 1913 and the balance on March 24, 1913. See 

 also Table 36 for the same kind of data on plum and cherry roots. 



Table 34. 



Showing Relative Hardiness of Various Parts of 

 the Root System of Fruit Trees. 



