2^42 EXPERIMENT STATION RECOED. [Vol.35 



tion where the P2 and succeeding generations were grown. A number of 

 crosses were made with the object of studying the unit characters found in 

 dwarf and standard varieties as well as to produce some superior commercial 

 variety. Data secured from various crosses of Fi and F2 generations are here 

 presented and discussed. 



Tomato growing in California, S. S. Rogers {California Sta. Circ. W {1916), 

 pp 12).— A revision of Bulletin 239 (E. S. R., 29, p. 540). 



Acreage of fruits in California, bearing and nonbearing, in 1915, G. P. 

 Weldon {Cal. Fruit News, 53 {1916), No. U50, p. 5).— A statistical compilation 

 showing the bearing and nonbearing acreage of various fruits and nuts in 

 California in 1915. 



Orchard management investigations, J. Oskamp {Proc. Soc. Hort. Sci., 12 

 {1915), pp. Jf4-Jf7).— In this paper the author briefly outlines an experiment in 

 orchard soil management which has been under way in southern Indiana for a 

 period of five years. No results are presented in this paper. 



Orchard economics, M. W. Richaeus (Proc. Soc. Hort. Sci., 12 {1915), pp. 

 47-50 ) .—A discussion of management costs reported from a representative apple 

 orchard included in the system of community demonstration orchards inaugu- 

 rated by the Purdue Experiment Station some five years ago. 



The water supply and fruit bud formation, W. Paddock {Proc. Soc. Hort. 

 Sci., 12 {1915), pp. 51-54). — In this paper the author reviews some data secured 

 in orcharding experiments at the New Hampshire Experiment Station (E. S. 

 R., 33. p. 44) with the view of showing that the amount of moisture present 

 in the gi-ound about the time when fruit buds begin to differentiate is an im- 

 portant factor in the development of fruit buds. 



The science of orchard heating, C. Nichols {Proc. Soc. Hort. Sci., 12 {1915), 

 pp. 22-27). — This comprises a brief review of the history of the development of 

 frost protection devices, including brief descriptions of a number of forms now 

 in use. 



The root systems of nursery apple trees, J. K. Shaw {Proc. Soc. Hort. Sci., 

 12 {1915). pp. 6S-72). — In this paper the author discusses chiefly the influence 

 of different apple scions on the root systems usually employed for grafting 

 apple trees. A number of observations based on an investigation of the 

 interrelation of root and scion in apples started at the Massachusetts Experi- 

 ment Station in 1912 are also presented. 



The results of apple pruning investigations, W. H. Alderman {Proc. Soc. 

 Hort. Sci., 12 {1915), pp. 54-59). — This comprises a preliminary report of experi- 

 ments started by the West Virginia Experiment Station in 1911 in which trees 

 in several orchards were given varying amounts of dormant pruning. The 

 results secured in the various orchards are here grouped together and discussed 

 with special reference to the effect upon vigor, growth, and fruitfulness of the 

 amount of pruning and season of pruning. 



Thus far the results secured indicate that heavily pruned trees do not make 

 as satisfactory a gain as lightly pruned trees, either in total length of growth or 

 in increase of trunk diameter. In young trees heavy pruning has delayed fruit 

 bearing and light pruning encouraged it. In old trees that have been bearing 

 for some time and were in a fair state of vigor at the beginning of the experi- 

 ment, the vigorous pruning stimulated fruit production. 



With reference to difference in season of pruning, in every case either heavy 

 or moderate dormant pruning stimulated a greater grov/th than any of the 

 summer primings. The reduction in vigor was less in the case of early summer 

 pruning than in either repeated or midsummer prunings. Summer pruning 

 caused a great decrease in the size of leaf, number of leaves per tree, and total 



