306 THE POMES 



pruning not only invites sun scald, but tends to induce 

 too strong and rank a growth. After the top of the pear 

 tree is formed, it is customary to do little pruning except 

 to keep the top free and open. As pears are borne on spurs 

 much like the apple, it is important in pruning that these 

 spurs are not removed unless it is desired to thin the 

 fruit. 



Varieties. Many pears produce infertile blossoms, 

 that is, they need the pollen of other varieties to cause 

 them to set fruit. In planting a pear orchard, it is, there- 

 fore, customary to plant not more than four consecutive 

 rows of one variety and to alternate with one or more rows 

 of another variety that blossoms at the same time and 

 produces an abundant supply of pollen. Some of the more 

 important commercial varieties of pears are the Bartlett, 

 Flemish Beauty, Clapp, Anjou, Bosc, Kieffer, Sheldon, 

 Seckel, and Le Conte. Of these varieties, the Bartlett is 

 the leading market pear, while the Kieffer being less sus- 

 ceptible to blight than most others, is used principally as 

 a canning pear. 



Quinces. -- The quince is a fruit of comparatively little 

 commercial importance. The fruit is used largely for 

 preserving, for marmalades, for jellies, and for flavoring 

 sauces made from other fruits. Its culture has reached 

 its highest development in the Northeastern States and on 

 the Pacific coast. 



Enemies of the Pomes. The principal insects that 

 injure the pome fruits are the codling moth, San Jose scale, 

 apple maggot, and apple curculio. Those that injure the 

 foliage are the tent caterpillar, cankerworm, web worm, 

 plant lice, and leaf rollers. Those injuring the trunk and 

 branches are the San Jose scale and apple tree borers. 



