The Effects of Radio-active Ores and Residues on Plant Life. 11 



SERIES 1 continued. 

 NOTES ON POTATO EXPERIMENTS. 



The tubers planted in sand showed signs of growth before those set in 

 soil, but the shoots were weak. 



A month after planting, the most forward sections were those dressed with 

 Coal Dust and with Lignaite. A fortnight later, however, they had dropped 

 behind, and the most robust foliage was seen in the trials dressed with Complete 

 Fertiliser. 



In these trials also it was noticed that some plants growing in soil treated 

 with Radium only were superior to those dressed with Radium and Farmyard 

 Manure. 



TRIALS IN SAND. 



Notes during Growth. When in full growth the plants with the 

 strongest foliage were found in the following sections : Complete Fertiliser 

 and Pure Radium Bromide, Controls with Complete Fertiliser and with Farm- 

 yard Manure, Vanadium Sand, McArthur's Sand, and Pitchblende Concentrates. 



The weakest plants were those dressed with Chemical Mixture and with 

 Pure Radium Bromide only. 



Between the remaining trials growing in sand it was difficult to observe 

 any difference. 



The unmanured Controls were especially good, considering that the plants 

 were growing in pure sand, but this is due to the fact that the Potato plant 

 can live for a long period on its own tuber. 



Final Notes. The weights obtained from the unmanured Controls 

 were (First) 8 Ibs. 9 ozs. and (Duplicate) 6 Ibs. 5 ozs. Seven of the trials 

 dressed with radio-active materials only gave a larger return than the First 

 Control (unmanured). The heaviest sections were the four Controls dressed 

 with Complete Fertiliser and with Farmyard Manure, with weights ranging 

 to 13 Ibs. 14 ozs., followed by Complete Fertiliser and Pure Radium Bromide 

 which gave 12 Ibs. 12 ozs. 



TRIALS IN SOIL. 



Notes during Growth. It was noticeable that in all the sections 

 to which Farmyard Manure had been applied the foliage of the plants was 

 paler in colour than in the remainder. In the trials dressed .with Complete 

 Fertiliser, the foliage exhibited a much bluer tinge than in any of the others, 

 and the plants were more branching in habit. 



At the period of full growth the strongest sections were the Controls 

 dressed with Complete Fertiliser, closely followed by Complete Fertiliser 

 and Pure Radium Bromide. The next best were the Farmyard Manure 

 Controls, and the tests with Nirama and McArthur's Sand. 



The weakest plants were those treated with Pure Radium Bromide alone. 



Final Notes. There was a yield of 12 Ibs. 8 ozs. from First Control 

 (unmanured), and from the Duplicate set 10 Ibs. 3 ozs., and the first-named 

 weight was exceeded in only two sections where Radium was used without 

 manure. The best weights were 16 Ibs. 4 ozs. and 14 Ibs. 2 ozs., from the 

 Controls dressed with Complete Fertiliser, and the lowest (7 Ibs. 3 ozs.) from 

 the Pure Radium Bromide test. 



13 Ibs. 14 ozs. 13 Ibs. 12 ozs. 11 Ibs. 2 ozs. 10 Ibs. 10 ozs. 9 Ibs. 1 oz. 8 Ibs. 9 ozs. Jibs. 13 ozs. 



DRESSING! Complete Farmyard Pitchblende Coal Radiiiii Control. Chemical 



USED. ) Fertiliser. Manure. Concentrates. Dust. R r r.miH Unmanured. Mixture. 



Potatoes grown in Sand. 



