540 EXPERIMENT STATION RECORD. [Vol. 43 



tlian 8 per cent of the seedlings luul superior fruit. Long keeping selections 

 of promise do not exceed a dozen. Some of the superior quality seedlings 

 are hardier than the standard varieties commonly grown in Minnesota. 



The occurrence of so many wild and inferior types as the result of open 

 pollination with superior varieties suggests that genetically the best varieties 

 of Fyrus tnaliis are heterozygous for a large number of characters, and that 

 a comparable number of wild and inferior types will be found even in con- 

 trolled crosses with the same varieties. 



Scion root production by apple trees in the nursery, J. G. Mooke {Proc. 

 Amer. Soc. Jlort. Sci., 16 (1919), pp. 8-'i-SS). — A contribution from the Univer- 

 sity of Wisconsin, reporting observations made of the behavior of grafts of 

 various varieties commonly grown in Wisconsin as regards scion root produc- 

 tion. The trees observed have been largely three year old nursery trees dug 

 during the years 1914-1918, inclusive. 



There were wide differences between the ability of different varieties to 

 produce scion roots. Generally speaking, varieties showing a relatively large 

 number of trees producing scion roots also show a relatively large number of 

 trees with " strong scion roots ;" but with most varieties, even after three 

 years in the nursery, the number of trees having sufficient scion roots to support 

 tiie tree is very small. • 



In addition to the varietal difference, the factors favoring scion root pro- 

 duction are an abundance of soil moisture, deep planting of the scions, and 

 probably the character of the union. Observations made indicate that when 

 poor scion unions occur, scion root production is encouraged. 



Progress in apple breeding for the Canadian prairies, W. T. Macoun and 

 M. B. Davis (Proc. Amer. Soc. Hort. Sci., 16 (1919), pp. 13-18).— A contribution 

 from the Central Experimental Farm, Ottawa, briefly reporting the present 

 status of the breeding work started by Saunders in 1894 (E. S. R., 25, p. 643). 



Crosses between the hardy Siberian crab apple (Pyrus haccata) and several 

 conunercial varieties used as male parents have resiilted in only two small 

 sized varieties of fair quality, the Columbia and Osman, both having Russian 

 varieties as male parents that have proved to be sufficiently hardy for the 

 most exposed and trying places in the prairies. It is suggested that these 

 varieties may yet play an important part in the development of hardy apples 

 for the prairies. 



In 1904 crosses were made on the most promising Fi seedlings, using 18 

 varieties of apples, with the view of retaining the character of hardiness 

 and improving the size of the apples. Several of these second crosses have 

 fruited at the experimental station at Morden, Manitoba. It is hoped that 

 some of them will be considerably hardier than the Russian apples and will 

 extend the area over which apples can be grown. Mcintosh has proved to be 

 a valuable parent in imparting quality and color to Fi crosses and has also 

 exerted some influence in increasing size. 



The results in general indicate that if a high-class progeny is desired at 

 least one of the parents should possess the desired character developed to the 

 highest possible degree of perfection. It is concluded that there must be more 

 blood of the P. baccata put into even the hardiest Russian apples to obtain 

 varieties that will withstand the severe tests on the Canadian prairies. Work 

 is to be continued, using P. haccata as the male parent rather than the female, 

 with the view of procuring at least a few hardy varieties of marketable size 

 among the Fi seedlings. 



Some notes on the inheritance of unit characters in the peach, C. H. Con- 

 nors (Proc. Amer. Soc. Hort. Sci., 16 (1919), pp. 24-36). — A contribution from 

 the New Jersey Experiment Stations, discussing character inheritance in the 



