1919] FIELD CROPS. 737 



chief advantages claimed for No. 38 are the quite erect leaves of uniform 

 size from top to bottom of the plant, being somewhat broader in proportion 

 to their length than ordinary Havana leaves; the presence of one or two 

 leaves more to the plant, on the average, than Havana, together with a 

 greater average size of leaf; and an estimated yield of from 7 to 10 per cent 

 more than ordinary Havana. The quality is said to be equal to, that of Con- 

 necticut Havana. It is also estimated that approximately one-fourth of the 

 total acreage devoted to tobacco in Wisconsin will be gi'own to this type in 

 1919. 



The Canadian water weed as a fodder plant (Jour. Bd. Agr. [London], 26 

 (1919), No. 3, pp. 321, 322). — The utilization of Canadian water weed or water 

 thyme (Elodea canadensis) for silage is briefly discussed. 



Harmful effects upon germination of the formalin treatment for seed, 

 L. KiEssLiKG (Jour. Landiv., 66 (1918), No. 1, pp. 1-51). — The author discusses 

 in considerable detail the eifect upon germination of dipping winter and 

 spring wheat and oats in formalin solutions of different strengths and for 

 varying lengths of time, together with observations on the effect of the treat- 

 ment upon injured grain and upon moist stored grain. 



[Proceedings of the American Seed Trade Association] (Proc. Amer. Seed 

 Trade Assoc, 30 (1918), pp. 126, pi. 1). — This comprises an account of the 

 thirty-sixth annual convention of the association held in Chicago during June, 

 1918. In addition to committee reports and other business the following 

 papers were presented and discussed : Seed Reporting as a Public Service, 

 by W. A. Wheeler ; Persistent Varietal Character in Garden Vegetables, by 

 W. W. Tracy ; The Home Garden as a Means of Increasing the Food Supply, 

 by W. R. Beattie ; Community Building in War Times, by A. K. Lovrien ; 

 and Some Immediate Responsibilities of the Seed Trade, by R. A. Oakley. 



Seed growing in Great Britain (Jour. Bd. Agr. [London], 26 (1919), No. 3, 

 pp. 318-321 ) . — This comprises a brief account of the industry in Great Britain 

 w'ith special reference to vegetable seed production. 



The control of weeds in field crops, E. Koesmo (Tidsskr. Norske Landhr., 26 

 (1919), No. 5, pp. 193-227, figs. 20). — This article discusses combating weeds in 

 field crops by means of seed treatment, cultivation, spraying, and fallowing, 

 and reports the results of a number of experiments along some of these lines. 

 Directions are given for the preparation of the solutions used in seed treatment 

 and spraying. 



In 1917, the results of experiments with wheat and rye showed the following 

 average increase in grain yield under the different methods of weed control : 

 Harrowing once before the plants appeared above ground 18 per cent, spraying 

 with iron sulphate solution 24 per cent, dusting with cyanamid 24.25 per cent, 

 spraying with sulphuric acid solution 28 per cent, and hand weeding 27 per 

 cent. 



Experiments were conducted for four years with potatoes for the comparison 

 of clean, ordinary, and no culture as affecting the percentage production of 

 large and small tubers as well as the starch content. Clean culture by means of 

 cultivation and weeding gave 83.5 per cent of large tubers, the removal of the 

 weeds without cultivation gave 81.2 per cent, ordinary culture 78.3 per cent, 

 and no cultivation or weeding during the growing period 39.1 per cent. The 

 starch content ranged from 15.8 per cent in the tubers grown under clean cul- 

 ture with cultivation and seeding to 16.5 per cent in those grown without any 

 cultivation or weeding. 



A similar series of experiments was carried on with turnips, kohl-rabi, and 

 carrots. Clean culture by means of cultivation and weeding gave on the average 

 29 per cent more turnips, 26 per cent more kohl-rabi, and 54 per cent more car- 



