84 CROSS-POLLENIZING THE FLOWERS. 



at the same time the pollen is by the wind or insects 

 carried to the flowers of other trees. The result is 

 the production of fruit with seeds related to both 

 parents, and so mixed and commingled that each 

 will have different characteristics, some producing 

 trees which are better, but generally those that are 

 inferior to either parent. It is in the selection of 

 these children that we have gained the excellent 

 varieties of our fruits and vegetables. 



The above supposes that nature has alone been 

 the agent of this cross-fertilization. Art has taken 

 the hint from her, and pursues a course suggested 

 by the known laws of vegetable life. 



In a work of this kind it is only necessary to treat 

 upon this from a practical standpoint. The lesson 

 to be drawn from it will be obvious. Mr. Wait, 

 of the U. S. Pomological department says: "The 

 factors affecting the production of flowers, are vari- 

 ety, age of tree, and vegetable condition, which is 

 influenced by the soil, culture, climate and pruning. 

 The factors affecting the setting of fruits are frost, 

 insect injuries, and sterility of pollen. Thus, 

 Bartlett and some other varieties of pears do not set 

 fruit when protected from the pollen of other trees. 

 Experiments were tried by fertilizing Bartlett with 

 Bartlett, but in no case did any fruit set. When 

 fertilized with Anjou and Clapp's favorite, good 

 results were obtained. Some pears will fertilize 

 themselves, but two thirds are self-sterile. Fruits 

 produced by self-pollenation aie quite different from 

 those produced by cross-fertilization. The crosses 



