lo Mar.. 1911-] /iiliueiice of Radio-active Minerals on Wheat. i^j 



Without attaching too mucii importance to the results which are not 

 entirely consistent, and would need to be repeated in two or three consecu- 

 tive years to obtain complete certainty, the radio-active mineral does ap- 

 pear to affect the weight of both the straw and the heads to some extent 

 when fairly heavy dressings are used. Thus, the average weight of the- 

 heads of all the plots treated with radio-active mineral in varying amounts 

 and combinations, was 118, whereas from those to which none of it was 

 added onlv a yield of 90 was obtained. The .■similar figures for the straw 

 were 369 and 362 respectively. 



It i.s certainly suggestive that plot 10, in which the radio-active mineral 

 was placed immediate!} under the .seed, gave, of all the plots, the biggest 

 yield of both the heads and straw. On the other hand, one of the radio 

 plots (No. 8) gave next to the poorest yield of both heads and straw, but 

 the fact that this plot was smaller than any of the. others, and that the 

 mineral was placed over the seed instead of l)elow it and close to it, may have- 

 .something to do with the low yield. The lowest yield of grain w'ould ap- 

 parently be given r»y the plot treated with the finely-ground phosphate 

 rock, and although the addition of the radio-active mineral apparently in- 

 creased the yield of straw, it seems as though it would have only slightly, 

 if at all, increa.sed the yield of grain. In the same way, comparing plots 

 6 and 7, the addition of radio-active mineral to .superphosphate, if any- 

 thing, decrea.sed the yield of grain. 



It is evident, however, from the careful study of the results, that no 

 conclusive results can as yet be dra^vn from them. They must be taken 

 merely as an indication that experiments in this direction may ultimately 

 vield interesting or even economically useful results, and that there is 

 a possibility that the addition of fineh divided radio-active minerals to 

 the .soil may influence the yield. Until, however, these experiments have 

 been repeated several times on both a large and small scale, and the ques- 

 tions of relative vield and cost have been fully considered, it would nf)t 

 1h- advisable for any farmer to spend a penny in the purchase of such 

 additions to the .soil. 



The Government Analyst (Mr. P. Rankin Scott) reports that the mineral 

 in question contains the following : — 



Per Pent. 

 Pliosplinrifi acid P.^O.-i ... ... ... 0-218 



P,.tash K.,() . " ... ... ... OIH) 



Calcinin ('aO ... ... ... ... 0-400 



Magnesia MgO ... ... ... 214 



It is evident, therefore, that neither the phosphoric acid. ])otash. calcium, 

 nor the magnesia, are present in sufficient amount to explain the 

 results ob.served, especially considering the fact that only a small part 

 of these constituents would be immediately available for the plant's u.se. 

 Any appreciable result produced by the addition of this mineral to the .soil 

 could therefore fairly be ascril)ed to the direct or indirect action of its 

 rarlio-activitv, 1 ut whether such results are constantly gi\en in field trials 

 is a matter for future determination. 



