Pollination 297 



Mutual affinities. — The question of mutual affini- 

 ties comes next in order. Do certain varieties have 

 special predilections with respect to pollen from other 

 varieties? This question in the eyes of many plum 

 students has seemed to be of great importance, and 

 the writer confesses once to have held strongly to this 

 prejudice. This theory is not confirmed, however, by 

 the evidence at hand; for while it is certainly true that 

 a given variety will sometimes accept the pollen of its 

 neighbor on the left and will not be pollinated by its 

 neighbor on the right, there seems to be no safe gen- 

 eral rule governing these selective affinities. In so far 

 as generalizations may be hazarded in this matter, they 

 may be summarized as follows: 



Japanese group. — These plums are readily polli- 

 nated by the varieties of almost any other group. The 

 least affinity seems to exist between them and the Do 

 mestica varieties. They are easily pollinated by the 

 Simon plum and by varieties of the Myrobalan or 

 Marianna class, but are especially apt to be pollinated 

 by members of the Chicasaw and Wildgoose groups. 

 This is so much the case that where the Japanese va- 

 rieties grow mixed with natives of the two groups 

 mentioned, almost every one of the seedlings from the 

 Japanese seed will show decidedly the Chicasaw or 

 Wildgoose characteristics. Ever since the Japanese 

 plums were first studied in this country by Bailey, it 

 has been understood that they were closely related 

 botanically to the groups now mentioned as their 

 ready pollenizers. 



Chicasaw group. — Many of these varieties are in- 

 ter-fertile among themselves, as indeed, seems to be 

 the case within most specific groups. They are also 

 readily pollinated by most varieties of the Wildgoose 

 type, or even by those of the Wayland type, where the 



