FIELD CEOPS. 137 



In no instance wns the difference between tlie biistiel weights of tlie grain 

 from any two of the plats very great. In all three series of experiments grain 

 of the highest bushel weight, 37f lbs., was obtained from the plats fertilized 

 with 1 cwt. sulphate of ammonia, 3 cwt. superphosphate, and 3 cwt. kaiuit per 

 acre. There was very little difference between the bushel weights of the samples 

 of grain from the plats manured with complete mixtures containing varying 

 quantities of superphosphate and kainit. The poorest quality grain was ob- 

 tained from the unmanured plats and that dressed with sulphate of ammonia 

 alone. Of the four nitrogenous manures nitrate of soda has produced the 

 lightest grain each season. The results from calcium cynanamid and nitrate 

 of lime wei'e identical. 



The potato question, L. Planchon (Bui. Sci. Pharmacol., 20 (1913), No. 12, 

 pp. 728-737). — In this paper the author reviews the most important literature 

 on the history, species, and the theory of mutation in Solatium tuberosum, 8. 

 maglia, and S. cotnmersonii. 



Potato spraying experiments at Rush in 1913, F. C. Stewart {New York 

 State Sta. Bui. 379 (1914), pp. S-9).— During the summer of 1913 an extensive 

 series of potato-spraying experiments was conducted in the vicinity of Rush, 

 N. Y. In each of 66 fields a portion of one row (one-fiftieth acre) was very 

 thoroughly sprayed by hand every two weeks. At digging time the yield of this 

 row was compared with that of an adjacent row which had not received the 

 special spraying. In 47 of the fields no spraying was done by the owner, while 

 in the other 19 fields more or less of such spraying was done. 



" In the 47 unsprayed fields the spraying done by the station increased the 

 average yield by 17.76 bu. per acre, or 16.4 per cent; and in the 19 sprayed 

 fields, by 1.5.04 bu. per acre, or 11.2 per cent. It is believed that the increase 

 obtained was due to the partial control of tipburn which was quite plentiful in 

 some fields, the better control of Colorado potato beetles (not well controlled 

 by the owner in a few cases), and stimulation of the plants. Late blight was 

 entirely absent and early blight and flea beetles scarce. Probably the gain 

 from spraying would have been considerably larger had not the plants been 

 killed prematurely by an early frost." 



Thoroughness pays in potato spraying, F. H. Hall (New York State Sta. 

 Bui. 379, popular ed. (1914), PP- 3, //). — A popular edition of the above. 



Prickly pear as a forage plant, J. E. Martinez (Bol. Dir. Gen. Agr. [Mex- 

 ico], Rev. Agr., 2 (1912), No. 10, pp. 90S-5i2).— Notes are given on the culture 

 of this plant as a forage crop in the State of Oaxaca. 



Preliminary note on the classification of rice in the Central Provinces, 

 R. J. D. Graham (Mem. Dept. Agr. India, Bot. Ser., 6 (1913), No. 7, pp. 209- 

 229, pis. 5). — This includes a description of methods of cultivation employed in 

 the Central Provinces, as well as preliminary notes on two schemes of classi- 

 fication of rices based on the agricultural and grain characteristics. 



Comparative fertilizer experiments with sulphate of ammonia and nitrate 

 of soda on winter rye in 1912, Wehnert (Landw. Wchnhl. Schles. Hoist., 

 64 (1914), No. 2, pp. 26-30). — With applications of sulphate of ammonia and 

 nitrate of soda to furnish equal amounts of nitrogen, rye yielded at the rate of 

 461 kg. per hectare with the latter and 633 kg. Vv^ith the former as the increase 

 over no application of nitrogenous fertilizers and the average of results at 

 10 centers. 



Silver beet: Its use as a forage crop, A. Macpherson (Neiv Zeal. Dept. Agr., 

 Indus., and Com. Bui. 36, n. scr. (1913), pp. 12, figs. 6). — A note on its cultiva- 

 tion and management as a forage crop of much promise. 



Possible economies in sugar production, W. R. Dodson (La. Planter, 52 

 (1914), No. 2, pp. 25-27). — This paper, read before the Louisiana Sugar 



