THE POLLINATION. OP ORCHARD FRUITS. 73 



THE POLLINATION OF ORCHARD FRUITS. 



PROF. F. A. WAUGH, BURLINGTON, VT. 



The pollination of orchard fruits as a practical question in 

 orchard management began to be discussed only about ten years 

 ago. A great many hints had been thrown out here and there 

 previous to that time, but no general theory seems to have been 

 suggested until the date of which I speak. The need of cross-pol- 

 lination was recognized by the fruit growers themselves, prob- 

 ably first with the native plums; and the fact that they are gen- 

 erally self-sterile was plainly set forth by Professor Bailey in his 

 Bulletin No. 38 of the Cornell Experiment Station, which was the 

 first satisfactory study we ever had of the plums native to America. 



The first scientific study of these questions, however, was made 

 by Mr. M. B. Waite, of the Department of Agriculture at Washing- 

 ton. His work was done chiefly with pears, although he experiment- 

 ed to some extent on apples. Briefly, he showed that many varieties 

 of pears require cross-pollination, and that many others yield larger 

 and better fruit when they are cross-pollinated. The publication 

 of Mr. Waite's results, along with many other things, contributed 

 to incite popular interest in this subject, and to induce a number 

 of experimenters to take up the question in many ways, from many 

 sides and with many fruits. 



My own work has been done chiefly with plums, and, although 

 I was preceded in this field by many other experimenters, some 

 of whom secured substantial results from their work, I think it 

 is not immodest to say that my experiments were the first ones of 

 special importance dealing with plums. What I have to say here 

 is necessarily based largely on my own experiments and practical 

 observations in the field. But I shall not confine myself to the 

 plum, and I shall try not to neglect the results brought out by 

 scientists and practical horticulturists in all parts of the country. 



THE PROBLEM STATED. 



The facts with which we have to deal are briefly stated as fol- 

 lows: Many varieties of orchard fruits, especially plums, pears and 

 apples, do not bear satisfactory crops when standing by themselves. 

 Some do not bear at all. The trees of such varieties require to 

 be mixed with trees of other more or less closely related varieties, 

 or they require to be grafted with a mixture of two or more varie- 

 ties. This general condition is summed up by saying that such 

 fruits are self-sterile, and, as we shall see, the problem of self-ster- 

 ility is the one with which we have chiefly to deal. 



