LUTHER BURBANK 



kill if grown on the high plateaus of Wyoming. 

 In general, it may be said that no region at 

 higher altitude than about six thousand feet is 

 adapted for fruit growing. 



In putting out catalogs of new fruit it is 

 often desirable to state the minimum temperature 

 that a new production will stand. I have done 

 this, for example, in announcing my spineless cac- 

 tus. As to average annual temperature, it may be 

 convenient to recall that there is likely to be a 

 mean annual difference of three degrees for each 

 hundred miles of latitude. Thus, for example, the 

 mean temperature at the southern line of Iowa 

 will be found to be about three degrees lower than 

 the mean temperature at the northern line; and 

 this difference might, in case of a given fruit, make 

 it folly to plant in northern Iowa a fruit that might 

 live in the southern part of the state. 



As already pointed out, however, one of the 

 main objects of the plant developer today is to 

 produce hardy varieties, and doubtless it will be 

 possible in the future to grow most varieties of or- 

 chard fruits in regions that are now regarded as 

 lying wholly beyond the northern limits of their 

 possible culture. 



STUDYING YOUR MARKET 



Of course the proximity of the market is an 

 item of chief importance. Yet the experience of 



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