450 Report of the Department of Horticulture of the 



A second reason for assuming that few varieties of apples 

 come from self-fertilized seed, is that the apple, in common with 

 many plants, loses vigor under self-fertilization and new varie- 

 ties are not likely to be selected from feeble seedlings. When 

 cross-fertilization is preferred by a plant, it may, generally 

 speaking, be assumed that the offspring of self-fertilized seed 

 "vvill be wanting in vigor, size and fertility. Two experiences 

 with inbred apples at this Station, while the number of trees 

 involved is too small to give the experiments much weight, are 

 suggestive as to the effects of inbreeding apples. 



One of these lots of trees consists of four seedlings from Hub- 

 bardston self-pollinated, which are and always have been, with 

 the best of care, but weaklings. None of these bore fruit until 

 in their fourteenth season and then two of them matured one apple 

 each. These Hubbardston seedlings are growing in the same 

 block under the same treatment as the crosses to be discussed, 

 which are wonderfully vigorous and productive. The weakness 

 and sterility of the selfed seedlings are so striking that it should 

 be counted as something more than a coincidence. The behavior 

 of these Hubbardstons may be compared with that of the crosses 

 in Table II, page 465. In 1907 several hundred Baldwin apple 

 seeds taken from fruits in an orchard in which no other varieties 

 were growing, were sown at this Station and though there was 

 a fair germination but 27 rather weak plants survive — the 

 others having succumbed to damping-off fungi, droughts and 

 cold. In the many different batches of apple seedlings grown at 

 this Station during the past six years, none have shown such lack 

 of vigor as these selfed Baldwins. 



From the fact that offspring of self-fertilized seeds have played 

 so small a part in the origination of varieties, and because of 

 the known consequences of close interbreeding, the use of selfed 

 seed does not promise much in breeding apples. 



Varieties from cross-fertilized seeds. — Although the data given 

 show that but one named variety is certainly known to be the 

 result of a cross, yet in spite of lack of exact knowledge it seems 

 certain that nearly all varieties of apples are crosses, because, 

 as has just been stated, apples normally prefer cross-pollination; 

 and selfed seedlings lack vigor and would largely be weeded out 



