630 EXPERIMENT STATIOIST RECORD, 



When considered per unit of carbohydrate consumed, the legnme bacteria fixed 

 us much or more nitrogen than Azotobacter. The gum produced by the legume 

 bacteria was found to contain little, if any, nitrogen. On culture solutions rich 

 in nitrogen the amount fixed was found to come from the medium and not from 

 the air. In a synthetic medium containing sugars the legume bacteria were 

 found to form small amounts of acid. Oxidizing enzyms ai-e present in the 

 gum of legume bactciia. It was found that bacteroid forms may be produced 

 by adding small amounts of caffein or cumarin to the culture medium. 



A bibliography of the subject is appended. 



A cultural and niorpholog'ical study of some Azotobacter, D. H. Jones 

 (Abs. in Science, n. set:, 38 {1913), No. 577, pp. ^13, 41^).— A brief account is 

 given of studies of 16 colonies of Azotobacter isolated from garden soil at 

 the Ontario Agricultural College. This study has been carried over a period 

 of 2 years and comprises 4 distinct varieties or species, 2 of which resemble 

 A. chroococcum; the other 2, A. agilis. 



The morphological characteristics of the different forms are described. 



The use of stains in the study of bacteria, E. B. Fred {Virginia Sta. Rpts, 

 1911-12, pp. 202-205). — ^A suggestion is given relating to the use of stains in the 

 study of bacteria, two groups of materials being recognized, one of which 

 contains stains that are reduced to a colorless compound, while in the other 

 group the reducing power of the fungi is measured by the color formation. 



Bibliography of smoke and smoke prevention; Effect on veg'etation, B. H. 

 McClelland (Mellon Inst. Indus. Research, Smoke Invest. Bui. 2, 1913. pp. 

 .58-71).— A bibliography of about 130 titles of publications relating to the effect 

 of smoke on plant life is given. 



FIELD CKOPS. 



[Field crops at the Fergus County substation], J. M. Stephens {Montana 

 Sta. Bui. 93, pp. 26-32). — In variety tests with potatoes, out of 45 selections the 

 highest average yields for 3 years, 1910-1912, were 147 bu. per acre by Green 

 Mountain and 144.5 bu. by Pink Eye. In variety tests with winter wheat, out 

 of 13 selections Kharkov gave the largest average yield of 40.72 bu. per acre, 

 followed by Turkey with 36.34 bu. The White Smyrna variety of barley gave 

 an average of 32.19 bu. per acre and Minnesota No. 105, 31.94 bu. as the best 2 

 out of 13 selections. Of spring wheats Fife produced an average of 27.17 bu. 

 per acre and Galgalos 24.34 bu. as the best 2 out of 21 selections. Of 19 selec- 

 tions of flax tested in 1911, Selected North Dakota No. 1214 produced 3,300 

 lbs. straw and 18.2 bu. grain per acre, and Selected Russian 3,200 lbs. straw 

 and 17.1 bu. grain. 



The results of tillage method tests during 1909-1911 showed fall plowing 7 

 in., double disking, and harrowing to give the best yield of winter wheat, 35.9 

 bu. per acre, of the several methods tried. With spring wheat subsoiliug, 

 double disking, and harrowing gave the best results, viz, 24.5 bu. per acre, 

 although this yield was closely followed (23.6 bu.) when the ground was spring 

 plowed 7 in., double disked, and harrowed. Oats yielded best on ground spring 

 plowed 3 in. and harrowed, 50.5 bu. per acre, followed closely by 49.6 bu.. 

 when listed and harrowed. Spring barley yielded 31.9 bu. on ground subsoil, 

 double disked, and harrowed, and produced 30.2 bu. by listing and harrowing, 

 which were considerably in advance of other methods. With corn there was 

 vei-y little difference in yields from land spring plowed 3 in. or 7 in., or sub- 

 soiled or listed, the yield being about 3^ tons per acre. Flax yielded 12.2 bu. 

 on land spring plowed 3 in. and harrowed, and 11.8 bu. when the land was 

 subsoiled, double disked, and harrowed. The introduction of fallow resulted 

 in lowering the 3-year average with each kind of crops grown. 



