THE KIND OF POLLINATION GIVING BEST RESULTS 53 



when self-pollinated. Many of our Pears, such as the Anjou 

 Bartlett, Pound, Lawrence, Jones, HoweU, Sheldon, Wilder, and 

 some others will not produce much fruit unless pollinated with 

 pollen from other varieties, while the Kiefer, Buffum, Seckel, and 

 some others known as self-fertile varieties set fruit well when 

 self-pollinated. Moreover, some trees which are self-fertile 

 develop larger and better fruit when cross-pollinated. {Fig. 58.) 

 Many of our Apple trees and Cherry trees are known to require 

 cross-polUnation . 

 Furthermore, some varieties of fruit trees i which require cross- 





Fig. 59. — Results of cross-poUination with different varieties in the 

 Sweet Cherry. A, fruit obtained by pollinating a cluster of flowers of the 

 Bing with pollen from the Black Republican. B, fruit obtained by polli- 

 nating a cluster of flowers of the Biag with poUen from the Knight. After 

 V. R. Gardner. 



pollination will not do equally well when crossed with all varieties. 

 In Apples, Pears, and Cherries better results have been obtained 



^ The poUination of pear flowers. Bulletin 5, Div. of Veg. Path., U. S. 

 Dept. of Agr., 1894. 



PoUination of the apple. Bulletin 104, Oregon Agr. College Exp. Sta., 1909. 



Pollination of the Sweet Cherry. Bulletin 116, Oregon Agr. College Exp. 

 Sta., 1913. 



Read Pollination in Orchards. Bulletin 187, Cornell University Exp. Sta., 

 1909. Also Pollination of Bartlett and Kiefer Pear. Ann. Report, Virginia 

 Agr. Exp. Sta., 1911. 



