228 POMOLOGY 



lower part of a tree may be entirely destroyed and those 

 above be unhurt and develop a crop. 



Paddock and Whipple discuss fruit-growing at high alti- 

 tudes as follows: "In a few favored locaUties peaches are 

 successfully grown at an altitude above 6000 feet. But on 

 the Eastern slope of the (Rocky) mountains no peaches are 

 grown commercially without winter protection where the 

 altitude is only 5000 feet. ... In general it may be 

 said that as a rule, fruit cannot be grown to any extent 

 at an altitude much above 5000 feet, and at this height 

 much depends on the protection afforded by the moun- 

 tains." 



198. Climate of United States. — Due to the extent of 

 territory comprised within the United States, there is a great 

 variety of climate, from the Arctic region on the northwest 

 to the semi-tropical climate of the south; yet the great pro- 

 portion of this country lies within the temperate zone. 

 However, as has been shown by Henry, ^ a great difference 

 exists in the length of the growing season as latitude and ele- 

 vation are changed and that this can be reduced to defi- 

 nite laws will be seen later. The map in Fig. 31 shows this 

 variation from a five months' season in the North to a twelve 

 month in the South. Such a condition makes evident that 

 climate will limit fruit-growing in certain sections except as 

 artificial means and certain cultural practices are employed 

 that will overcome the natural barriers. 



Any statistical statement of meteorological data would 

 be too extensive for use here, but the student should fa- 

 miliarize himself with local conditions. The extremes of rain- 

 fall and temperature will serve to emphasize the wide diver- 

 sity within the borders of the United States. These data 

 may best be examined in connection with the several so- 

 called climatic provinces of the United States. 



'Henry, A.J. Weather Bur. Bull. Q. Washington, D. C. 1906. 



