196 



PLANTS AND MAN 



peared as a chance variety in Excelsior, Minnesota in 1894. The 

 common crab apple is a hybrid of the orchard apple and the 

 Siberian crab apple. 



Apples, in addition to being eaten as a fresh fruit, have a 

 variety of other uses. A large proportion of the crop is made into 

 cider and vinegar. Conversion of cider into vinegar involves two 

 kinds of fermentation; first, the sugary solution of the cider is 

 converted into alcohol by the action of yeast, then the alcohol is 

 transformed into vinegar by the activity of acetic acid bacteria. 

 Some of the crop is also made into dried apples, used for domestic 



consumption and export to Germany 

 and Holland. In making dried apples, 

 the fruit is cored and sliced, dipped in 

 weak salt solution, bleached with sul- 

 phur fumes and then tray-dried while 

 hot air under pressure is passed over 

 them. In some localities apples are used 

 as livestock feed. 



Pears are closely related to apples, 

 being considered by some botanists to be 

 merely different species of the same 

 genus. Pear trees are straighter and 

 taller than apple trees and bear white 

 flowers which appear before the leaves. 

 The pear is an accessory fruit like that 

 of the apple, being derived from a fleshy 

 receptacle which surrounds the core or 

 enlarged ovary (fig. 133). The pear is 

 a juicier fruit and therefore does not keep as well as apples, and is 

 easily bruised in shipment or storage. The flesh is character- 

 istically gritty due to the presence of minute stone cells (scleren- 

 chyma). There are no native American species, all of the 

 cultivated pears being derived from southern European and 

 Asiatic plants. They are referred to in the writings of the early 

 Egyptians, Syrians and classical authors. Pears, being less hardy 

 than apples, have a more restricted range; the trees thrive on 

 heavy humus soils with good drainage. The chief pear-raising 

 country is France. In the United States pear orchards are suc- 



FiG. 133.— The pear 

 is an accessory fruit like the 

 apple. 



