abstracts: agronomy 661 



PLANT PHYSIOLOGY. — Boron: its effect on crops and its distribu- 

 tion in plants and soil in different parts of the United States. F. C. 

 Cook and J. B. Wilson. Journ. Agr. Res. 13:451-470. May 

 27, 1918. 



This is the final paper of a series of three deahng with this subject. 

 The influence of borax (sodiuni borate) and of calcined colemanite 

 (calcium borate) was studied on various cultivated plants. The ex- 

 periments in some cases extended over three years and the maximum 

 amount of borax used was in excess of that which truck growers, in 

 applying manure treated with borax to kill larvae of the house fly, 

 might possibly add to their cultivated fields. Soils showed a decided 

 difference in rendering the added borax nontoxic to plants. There was 

 a complete disappearance of detectable amounts of soluble borax and 

 of colemanite, although small amounts of total borax were found. It 

 is evident that insoluble borax compounds are formed in the soil. The 

 calcium of the colemanite did not prevent the absorption of borax by 

 the plants. 



The amounts of borax absorbed seemed to vary with the variety of 

 plant, the solubility of the borax compound used, the amount added 

 to the soil, the time elapsing after the compound was added to the 

 soil before planting, the amount of rainfall, etc., and finally with the 

 character of the soil to which the borax compound was added. 



The distribution of the borax in different parts of the various plants 

 was investigated and results showing the influence on the yield of some 

 of the crops are included. F. C. C. 



AGRONOMY. — Effect of temperature and other meteorological factors on 

 the growth of sorghums. H. N. Vinall and H. R. Reed. Journ. 

 Agr. Res. 13: 133-148, pis. 11, 12. April, 1918. 



The purpose of this study was to determine the reactions of the 

 sorghum plant to climatic conditions. Several varieties were grown 

 under field conditions at Chillicothe, Texas; Bard and Chula Vista, 

 California; and Puyallup, Washington. The average of the monthly 

 means of temperatures for the growing seasons at the above points was 

 75.6°, 81.8°, 62.4°, and 60.4° F., respectively. The percentage of ac- 

 tual to possible sunshine was 75, 93, 68, and 46. The total degrees of 

 positive temperature received by the sorghums at Chillicothe was 

 3028°, at Bard 4236°, at Chula Vista 1895°, and at Puyallup 1615° F. 



None of the sorghums matured at Puyallup, but all matured at Chula 

 Vista with only 280° difference in the total of positive temperatures. 



