VARIETIES OF PEARS STUDIED. 



41 



Tke work on the Bartlett denioiistrated tliat in the majority of eases 

 it is neailyor quite sell-sterile. In Series I, II, and IV no self- pollinated 

 fiuits whatever were secured, while in Series III only a few Avere 

 obtained. The study of the cross and self -pollinated fruits, given on 

 pp. 60-05, develops the fact that the self-pollinated pears are quite 

 different in shape from the crossed, so much so that they can be readily 

 distinguished, and that the fruits from the trees at large are almost 

 invariably crosses. The trials made at Chestnut Farm with different 

 kinds of Bartlett pollen and the general experience in that orchard have 

 shown that it is a cross from a different variety that is needed, and that 

 individual crossing, even of two different trees of the same variety, is 

 no better than self-pollination from the same flower. It is desirable to 

 test this latter point still further and under conditions more favorable 

 to self-fertilization than they were at Chestnut Farm, th# conditions 

 there being such that no fruits whatever were secured without true 

 crossing. Judging from the results obtained, self-fertilization or indi- 

 vidual crossing, that is, Bartlett pollen for Bartlett fruits, must be 

 regarded as very unsatisfactory and uncertain. Possibly when the 

 most favorable conditions of soil, climate, cultural methods, and weather 

 duiing the flowering time i)revail, the Bartlett might be able to fruit 

 satisfactorily as a self-fertilizer, but this is very doubtful. There could 

 hardly be expected more favorable conditions than those under which 

 the experiment was tried at Rochester in 1892, so that self-fertilization 

 is probably there shoAvn at its best. It has been proved that cold 

 weather during the flowering period renders some jflants incapable of 

 self- fecundation, although they still retain the ability to be cross- 

 fecundated. Very likely the cool weather during the flowering period^ 

 at Brockport in 1891 and at Chestnut Farm in 1892 helped to make the 

 flowers completely self- sterile. 



Of the various kinds of pollen applied, Angouleme, Anjou, Clapps 

 Favorite, Easter, Sheldon, and White Doyenne gave excellent results, 

 and although these varied considerably, still the differences were not 

 greater than when the pollen of one variety was applied to different trees, 

 so that the variations are within the range of accident. Seckel and 

 Le Conte pollen gave poor results, but should be investigated further 

 before being rejected. I^^^one of the six fruits recorded as set on tree 

 ^To. 50 (Seckel pollen) reached maturity. Accidents may, however, have 

 caused this. Probably most of the common varieties of pears will prove 

 good fertilizers for the Bartlett. It should be noted that Bartlett pollen 

 is capable of fecundating other varieties, for example, the Anjou {see 

 trees Nos. 15 and 16). The Anjou and Bartlett are both more or less 

 self-sterile, but the pollen of each is fertile on the other. Doubtless this 

 is the general rule among all the varieties. It is the cross that is needed. 

 The pollen may come from a self-sterile or a self- fertile sort and still be 

 equally effective. 



