FIELD CROPS, 139 



beneficial effect as clue to the direct liberation of plant food rather than to its 

 neutralizinii or other action. 



Experiments with hybrid cottons, J. N. Harpee {South, Carolina Sta. Bal. 

 I'/S. 1)1). UK pis. 6). — This bulletin is a pi'ogress report of breeding work with 

 cotton. It outlines the methods used and gives a brief history and statement 

 of the important characteristics of each of the varieties worked with. The 

 maximum yield of 2,46!"> lbs. of seed cotton per acre was produced by the Ninety 

 Day cotton, an early variety with bolls of medium size. 



Som.e conditions influencing' the yield of hops, W. W. Stockberger and J. 

 Thompson {U. S. Dcpt. Agr., Bur. Plant Indus. Circ. 56, pp. 12, figs. 2). — A 

 study was made as to the conditions on an acre of hops in California selected as 

 representative of 600 surrounding acres. This study showed that nonproductive 

 and missing hills reduced " the actual yield to 87.9 per cent of what might be 

 expected of a perfect stand." Individual hills varied in yield from 0.5 to IS lbs., 

 while the average yield per hill was G.104 lbs. 



"As the number of vines per hill increased, the average yields of the hills 

 having the same number of vines were found to increase in approximately the 

 same ratio. Assuming a full stand of 957 hills with 6 vines trained to each hill, 

 the calculated possible yield is 65.2+ per cent greater than the actual yield on 

 this acre. 



" ' Bastard ' or ' mcmgrel ' hills should be dug out and destroyed, as they are 

 of no value and diminish the total yield." 



Field peas, L. B. McWethy {Wgoming Sta. Bui. S.'/. pp. 11, pis. 3).— The 

 climatic and cultural requirements of field peas are stated and directions given 

 for harvesting. In a variety test French June (19389) produced the maximum 

 yield, 21.45 bu. per acre, and ripened earlier than any other variety. 



A variety test of potatoes, C. F. Noll {Pennsylvania Sta. Bui. .98, pp. 3-20, 

 figs. ^). — The average yields of varieties tested during the period 1906-1909, 

 inclusive, ranged from 48.5 to 181.5 bu. of marketable potatoes per acre. The 

 varieties giving the highest average yields were Six Weeks and Pride of 

 Michigan for the early varieties, Early Puritan and Early Rose for the medium 

 late varieties, and Heath Medium Late Surprise and Whiton White Mammoth 

 for the late varieties. The results of the tests during each of the 4 years are 

 I)resented in tabular form and descriptive notes are given of some of the 

 varieties. 



Planting potatoes, S. Tretyakov {Khutoryanln, 1909, Xo. l.'t; ats. in Zhur. 

 Opuitn. Agron. {Russ. Jour. Expt. Landw.), 10 {1909), No. Jt, p. 580). — Larger 

 yields were obtained when the tubers were planted whole than when cut. 



Fertilizers for potato soils, M. Whitney {U. S. Dept. Agr., Bur. Soils Bui. 65, 

 pp. 10). — This bulletin gives a compilation of yields of potatoes on fertilized 

 and unfertilized soils obtained in 1,769 tests reported by 23 of the state agri- 

 cultural experiment stations. 



Although there was considerable variation in yield of the check plats of the 

 same field there appears to be good chance to obtain an increase in the crop 

 by the application of fertilizers, especially by the application of 2 or 3 sub- 

 stances rather than of a single substance. Little indication was observed of a 

 significant difference in productivity due to different amounts of fertilizers 

 used or of a significant difference in effectiveness of fertilizers on soils of dif- 

 ferent natural productivity. 



In the author's opinion, the data reviewed do not permit a judgment as 

 to the cumulative effect of the continued use of fertilizers for a long period. 

 The re.sults generally indicate a profitable use of fertilizers in growing potatoes. 

 48507°— No. 2—10 4 



