Fruit Setting and Pollination 255 



increase the set. Darwin states: "Nature abhors self- 

 fertilization." 



ESSENTIALS EO'B A GOOD POLLINIZEE 



The following points should be considered in selecting 

 varieties for pollination: (1) Not more than one row in 

 six is necessary to insure certainty of proper pollination 

 under normal weather conditions and in the presence of 

 pollinizing agents. However, attention is called to the 

 fact that varieties to be handled economically should occur 

 in plantings of at least two or three rows. (2) Varieties 

 should bloom at the same time. This is clearly necessary, 

 otherwise the pollen of one variety would be entirely gone 

 before the other bloomed, making cross-pollination impossi- 

 ble. (3) Varieties must have an affinity for each other; 

 that is to say, the pollen of one must be acceptable to the 

 pistils of the other. It is well in this connection to men- 

 tion the fact that pears will not serve to pollinate apples 

 or vice-versa. (4) Varieties must be good pollen-pro- 

 ducers. If varieties which produce little pollen are 

 planted with those producing abundant pollen, the former 

 but not the latter will be benefited. It is important here 

 to mention that Winesap is a very shy pollen-producer and 

 should not be planted for the purpose of pollinating other 

 varieties. (5) Varieties should come into bearing at 

 about the same age. Such kinds as the Northern Spy 

 would not immediately serve as pollinizers for the Wagener 

 or Twenty Ounce, since the former is an extremely late 

 bearer. (6) The varieties should be commercial. While 

 this is not at all necessary so far as cross-pollination is 

 concerned, it is highly important from a commercial stand- 

 point. It is clearly inadvisable to plant non-commercial 



