46 



when there were any pears in that section and the drooping 

 branches of these trees testified to the truth of the mana- 

 ger's statement respecting this. The same experiments were 

 tried here as in the New York orchards. Also much cross 

 pollination by hand was done. In no case where Bartlett 

 pollen was applied to Bartlett pistil did fruit set, while a 

 very large per cent of the flowers cross-pollinated set fruit. 



Mr. Waite also investigated the apples, using the same 

 methods as with pears. He found that a very large per 

 cent of the varieties were either self-sterile or only partially 

 self-fertile. 



Mr. Fletcher's * work extending over a period of three 

 years in both Michigan and West Virginia corroborrates 

 Mr. Waite 's results with respect to Keiffer and Bartlett 

 pears. Mr. Fletcher confined his efforts to these two varie- 

 ties and the results from the thousands of blossoms experi- 

 mented with should be conclusive. Neither of these 

 varieties show sufficient self-fertility to warrant setting 

 them without provision for cross-pollination. 



In 1897 Professor Waugh at that time with the Vt. Exp. 

 Station **began a series of experiments with plums to 

 determine if they were self-fertile or self-sterile. Some of 

 this work was done in Vermont and some in the large 

 'Orchards of Mr. Kerr of Denton, Maryland. 



His method of procedure was essentially the same as 

 that of Mr. Waite. Large clusters were enclosed in paper 

 l^ags. When the pistils were receptive some of the bags 

 were removed and the flowers hand-pollinated with the 

 pollen found in the bag or in enclosed flowers. The remain- 

 ing bags were allowed to remain until petals had dropped. 

 No appreciable difference was noticeable in these two 

 methods of treatment. Altogether some 55 varieties of 

 native and 5 varieties of Japanese plums were tested. The 

 results show that for all practical purposes all species of 

 native plums are absolutely self -sterile, and while it is gener- 

 ally believed that some varieties of the Jajaanese group are 

 self-fertile the varieties here tested were self-sterile. All 



*Va. Exp. Sta. Rept. 1909-'10. 

 **10th, 11th and 12th An. Rept. 



