May 27, 1918 



Boron 



459 



when added at the 24-ton rate reduced the yield markedly over the yield 

 on the plots fertilized at the 16-ton rate. With the control the reduction 

 of the 24-ton over the 16-ton plot was proportionately greater than with 

 the 40-ton over the 24-ton plot. With the boron-treated plots the marked 

 action of the 40-ton applications is shown by the practical destruction of 

 the bean crop and the marked reduction of the yield of corn. 



Table VIII. — Weights of one row of whole bean and corn plants at Arlington Experi- 

 mental Farm, igi^ 



Boric add added to upper 6 inches of soil. 



Per cent 



0.00176 as borax (16-ton plot) 



0.00264 as borax (24-ton plot) 



0.0044 as borax (40-ton plot) 



0.00232 as colemanite (16-ton plot). 

 0.00348 as colemanite (24-ton plot). 

 0.0058 as colemanite (40-ton plot). .. 



16-ton control 



24-ton control 



40-ton control 



Com. 



Lb. 



37 

 17 

 14 

 54 

 21 



15 

 48 



29 

 30 



On October 5 samples of turnips from the 1 6- and 40- ton borax- treated 

 manure plots and from the 40-ton control plot were collected and tested 

 with the results given in Table IX. 



Table IX. — Percentage of boron in turnips, dry basis, at Arlington Experimental Farm, 



1915 



Boric acid added to upper 6 inches of soil. 



Per cent. 



0.00176 as borax (i6-ton plot) 



0.0044 as borax (40-ton plot) 



40-ton control 



Parts of plants 

 analyzed. 



/Tops. 

 IRoots 

 /Tops. 

 \Roots 

 /Tops. 

 \Roots 



Total boron 



as boric 

 add found. 



Per cent. 

 O. 0036 

 . 0012 

 .0032 

 . 0017 

 . 0020 

 . 00002 



The tops contained the greater portion of the boron. The boron in the 

 roots varied directly with the boron added to the soil, whereas in the tops 

 this was not the case. On comparing these results with the results re- 

 ported in Table VI for the plants grown on these plots after the first 

 application of manure containing added boron, it is evident that no more 

 boron was taken up by the turnips grown after the second application of 

 boron-treated manure than by the plants after the first application. 



Samples of soil were taken from these plots on October 5 and tested 

 for solids, nitrate and ammonia nitrogen, and total and soluble boron. 

 The results are given in Table X. 



