May 27. 1918 Boron 463 



The 24-ton borax treatment decidedly injured both beets and beans, 

 but no injury to com or potatoes was apparent. On the 24-ton cole- 

 manite-treated plot beans were injured considerably and beets slightly, 

 while com and potatoes were normal. 



The 40-ton borax treatment injured all the plants; beans and beets 

 severely and com and potatoes slightly. The 40-ton colemanite treat- 

 ment injured beans and beets only. The 40-ton control plot did not 

 produce as good crops as the other control plots. 



The corn on all control plots showed the highest stand, although the 

 other plots showed no apparent injury. The potatoes showed no injury, 

 except a slight yellowing of the leaves on the plants grown on the 40-ton 

 borax-treated plot. 



During October, 191 5, the crops were harvested and samples from 

 each plot were taken for analysis. Soil samples 6 inches deep were also 

 taken from each plot at this time. The potatoes from the three borax- 

 treated plots made 3X bushels, from the three colemanite-treated plots 

 2}^ bushels, and from the three controls 2>^ bushels. Analyses of 

 potatoes, com, beets, and string beans from several of the plots are 

 given in Table XL It is evident from this table that the plants grown 

 on the 24- and 40-ton borax-treated plots took up slightly more boron 

 than those grown on the 16-ton borax-treated plot. The roots and tops 

 of the potatoes contained more boron than the tubers in all the samples 

 tested. The corn showed the presence of boron in the ears only. All 

 of the beet samples analyzed showed the presence of minute amounts of 

 boron in the roots, but none in the tops. The string beans and pods 

 were analyzed together. Separate analysis of tops and roots were made. 

 The tops contained more boron than the roots, and the beans and pods 

 the least. The beans did not seem to take up the boron in proportion to 

 the amounts added to the soil, as less boron was found in the plants 

 grown on the 40-ton than in those on the 16-ton plots. The amounts 

 found were small in all cases, owing to the fact that the samples were 

 taken in October and the severely injured plants, which contained the 

 comparatively large amounts of boron, had died earlier. 



Peligot (8), in 1876, tested the influence of boron on beans. He used 

 borax, boric acid, and potassium borate, 2 gm. per liter. The leaves 

 turned yellow and all the plants were killed. 



Haselhoff (5) grew beans in culture media containing borax and boric 

 acid. A spotting of the leaves was observed, but this does not neces- 

 sarily indicate an injury to plant growth. Boron was detected in the 

 straw, but not in the beans. 



The figures for solids in beans and pods showed higher, results for the 

 treated than for the control samples. 



