1917] FIELD CROPS. 533 



grown at the station, producing as high as 24 tons of green forage per acre. A 

 rate-of-seeding test with Japanese sugar cane in 1914, using rates of approxi- 

 mately SOO, 2,000, and 4,000 lbs. of cane, gave yields estimated at 19,226, 

 27,687, and 36,524 lbs. per acre, respectively. 



An experimental planting of Bermuda grass, burr clover, and Lespedeza is 

 reported to have given good results in a test of pasture mixtures begun in 

 3911 and 1912. 



[Field crops], C. A. Zavitz {Ann. Rpt. Ontario Agr. and Expt. Union, 57 

 (1915), pp. 12-38). — This is a report of cooperative field experiments in On- 

 tario with different varieties of grain crops, roots, forage and silage crops, and 

 fertilizer tests with potatoes, mangels, and rape for the year 1915. 



Cultivated plants. Potatoes and sugar beets, H. Hitier {Plantes .S'orc/cJe.v. 

 Vomme de Terre et Betterave. Paris: J. B. Bailli<}re d Sons, 1916, pp. Jf9S, figs. 

 26). — This work is presented in two sections, one dealing with potatoes and the 

 other with sugar beets, each crop being discussed in considerable detail. 



Contribution to the study of Gramineae, C. D, Girola (Bol. Min. Agr. [Ar- 

 gentina], 19 {1915), No. 10-12, pp. 867-874, fig. i).— Some notes are given on 

 Sporobolus phleoides, including chemical and physical analyses. 



The relation of winter temperature to the distribution of winter and 

 spring grains in the United States, S. C. Salmon {Jour. Amer. Soc. Agron., 

 9 {1917), No. 1, pp. 21-24, figs. 2). — This paper discusses some studies begun 

 during the winter of 1913-14, at the Kansas Experiment Station, to determine 

 the relation between winter temperatures and the distribution of winter and 

 spring grain in the United States. The data have been collected from the 

 Census reports and Weather Bureau records of the United States and Canada. 

 Two outline maps of the United States and Canada, upon which isotherms 

 have been plotted, illustrate the distribution of winter and spring wheat. The 

 isotherms connect points of equal daily minimum temperature for January and 

 February. 



The isotherm of 10° F. coincides with the line which divides the winter from 

 the spring wheat belt. Practically the only exception is where spring wheat 

 is grown south of the isotherm, rather than where winter wheat is produced 

 north of it. 



The isotherms of 20 and 30° coincide very closely with the northern limits 

 for winter barley and winter oats, respectively, agreeing with the statements 

 of Derr (E. S. R., 28, p. 432), Stephens (E. S. R., 32, p. 730), and Wa^burton 

 (B. S. R., 25, p. 133). 



The absence of any correlation between the northern limit of winter cereal 

 culture and snowfall is noted, and may be due to the fact that heavy spring 

 snows, increasing the moisture content of the soil, increase the danger from 

 heaving, thus offsetting the protection afforded by earlier snows. 



The effect of greenhouse temperatxires on the growth of small grains, T. B. 

 HuTCHESON and K. E. Quantz {Jour. Amer. Soc. Agron., 9 {1917), No. 1, pp. 

 17-21, pis. 2, figs. 1). — This paper reports the results of an experiment con- 

 ducted by the authors during the winter of 1915, at the Virginia Agricultural 

 Experiment Station, to test the effect of temperature upon winter wheat, oats, 

 barley, and rye grown in greenhouses. The greenhouses were kept as near the 

 following temperatures as outside influences would permit: House No. 1, 75° F. ; 

 house No. 2, 65° ; house No. 3. 62° ; and house No. 4, 58°. The seeds were sown 

 in 4-in. earthen pots on December 21, 1915, and the experiment discontinued 

 May 27, 1916. The results of the experiments showed the effects of temperature 

 to be as follows : 



Except in the case of oats, the cool temperature produced earlier maturity, 

 while high temperatures stimulated rank growth of tillers and thus wasted 



