1917] FIELD CROPS. 435 



animal from which they are named as regards adaptation to extreme special 

 conditions. 



A quantitative, volumetric, and dynamic study of the vegetation of the 

 Pinus taeda belt of Virg-inia and the Carolinas, R. M. Harpee {Bui. Torrey 

 Bot. Club, U U917), No. 1, pp. 39-57, fig. J).— This is an account of a very 

 rapid survey of the P. tceda belt of the Atlantic coastal plain as regards its 

 boundaries, topography, hydrography, soils, climate, and vegetation, giving lists 

 of plants observed with estimated percentages of the several species. 



Meadow vegetation in the montane region of northern Colorado, E. L. 

 Reed (Bui. Torrey Bot. Club, U (1917), No. 2, pp. 97-109, fig. i).— The results 

 of studies made during two summer seasons are embodied chiefly in descrip- 

 tions of seven plant societies of meadows of the Boulder Park region, at Tol- 

 land, in northern Colorado, with an altitude of 2,710 meters (8,891 ft.). 

 Societies of the lower montane region are indicated and the different charac- 

 teristics of the subalpine meadows are also briefly discussed. A list of the 

 meadow plants of Boulder Park with their frequency and soil moisture index 

 is also given. 



Taxonomic botany and the Washington botanist, A. S. Hitchcock (Jour. 

 Wash. Acad. Sci., 7 {1917), No. 9, pp. 251-263).— This is a plea for a better 

 utilization of the opportunities in the vicinity of Washington, D. C, as re- 

 gards observation and taxonomic study of local flora. 



FIELD CKOPS. 



Forage and root crops, C. S. Knight {Nevada Sta. Bui. 86 (1917), pp. 3-20, 

 figs. 13). — Variety tests with alfalfa, corn (for silage), sorghum, and potatoes; 

 irrigation tests with alfalfa and red clover; field tests of sweet clover, Sudan 

 grass, and beets and mangels ; and tests of forage crops for seed and hay 

 production are reported. 



Australia alfalfa No. 23753 was first of M varieties with a yield of 6,920 

 lbs. and North Dakota No. 27247 second with 6,875 lbs. of cured hay per acre. 

 The proportion of leaves to the entire plant was 36.8 and 36.5 per cent, re- 

 spectively. Nevada No. 6 was lowest with a yield of 2,100 lbs. The propor- 

 tion of leaves to stems for all the varieties tested varied from 48.5 per cent in 

 France No. 12694 to 30 per cent in Media No. 16400, although the yields of the 

 two varieties named were identical, 3,004 lbs. of hay per acre. 



Improved Leaming corn gave the highest average yield of silage per acre, 

 11.3 tons, for the 4-year period 1913 to 1916. Wisconsin Yellow Dent, with a 

 yield of 8.5 tons, was lowest. No variety has matured grain. 



The sorghums did not mature seed and were considered inferior to corn for 

 silage purposes. Broom corn produced a heavy brush, but did not mature seed. 



The Great Divide and Burbank varieties of potatoes, with average yields 

 of 12,161 and 10,204 lbs. per acre, respectively, have given the best results in 

 potato variety tests for the 4-year period 1913 to 1916. 



Irrigation tests with alfalfa and red clover included 6, 9, and 12 in. applica- 

 tions of water at three successive stages of wilt. With the advance in the 

 wilting stage, the average variations in alfalfa for a 3-year period were from 

 64 to 21 in. in total irrigation, 83.9 to 76.4 per cent in total water content, 

 37.3 to 43.2 per cent iu proportion of leaves to stem, 6.68 to 4.41 tons in yield 

 per acre, and 1.29 to 2.05 tons in yield per acre-foot of water. The heaviest 

 yield per acre, 7.32 tons, was secured with the heaviest total irrigation of 72 

 in., but the yield per acre-foot of water was only 1.23 tons. These results 

 indicate that the most economical use of water favors 12-in. applications (with 

 a total irrigation of about 36 in.) between the last two stages of wilting, this 



