VARIETIES 



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frequently practiced as a thinning process, but in addition 

 to this, hand thinning is often necessary. 



Varieties. The Elberta is the standard market variety 

 in most of the Northern States. Its productiveness, hardi- 

 ness, and general characteristics make it a most profitable 

 commercial variety. St. Johns, New Prolific, Triumph, 

 Engle's Mammoth, Alexander, Greensborough, Gold Drop, 

 Smock, and Lemon Free are other important varieties. 



Plums. Plums are an important commercial fruit, 

 especially in localities where the climate is too rigorous for 

 peach production. Large quantities of plums are canned, 

 and in many sections the fruit of one class is dried for 

 prunes. In seasons when the peach crop is short, the de- 

 mand for plums is correspondingly increased. 



Varieties. There are probably more species of plums 

 grown in this country than of any other fruit. The Euro- 

 pean plum is best known in the Eastern States, although 



Fig. 167. A plum orchard on an ideal site. The well-cultivated ground slopes off 



to the lake. 



