AND ITS ADAPTABILITY TO LATITUDES. 3$ 



purpose. Even if they recorded the lines of mini- 

 mum temperatures across the country, they would 

 then be evidence of this condition only and might 

 not even approximate those larger conditions which 

 govern the adaptability of varieties. We know it 

 to be true that certain varieties of plums are tender 

 in northeast Nebraska that are successfully grown 

 much further north in South Dakota, and the same 

 is true of varieties of apples that are tender or half 

 hardy in central and southern Iowa that are success- 

 fully grown in northern Nebraska. Some of these 

 are Wolf River, Pewaukee, Northwestern Greening, 

 Iowa Blush, Ben Davis, and others of about this 

 class of hardiness. 



The larger conditions which control, or balance 

 those of latitude, or even of minimum temperature, 

 are many, such as soil, altitude, humidity (such as 

 proximity to water, or rainfall) wind currents or 

 maximum temperatures. These are general causes, 

 and may, singly or when combined to a still 

 greater degree move the fruit belt north to its 

 advantage through two or more degrees of latitude. 



Then there are local causes in which the removal 

 of the tree but a few miles may have a greater 

 effect upon it than the removal of 100 miles under 

 different conditions, such for instance as the 

 removal from the south to the north side of the 

 hill or from the top to the bottom of a bluff. 



The manner of pruning the tree, too, will exert 

 much influence upon its hardiness; as in the case of 

 the Wealthy, which is very close to the Duchess in 



