420 Joiinial of Agriculture, Victoria. [lo July, 1912. 



In the case of the two plots A, owing to the smaUness of them, only 

 a few samples could be taken. A subsequent microscopic examination from 

 the Longerenong plot A showed the presence of an unusual amount of 

 decaying \egetable n:atter, which is probably the explanation of the un- 

 usually high number of organisms. The Longerenong samples were also 

 tested on agar at body temperature. The sample A then appeared to con- 

 tain fewer organisms than B, C, and D, and they consisted mainly of 

 Bacillus subtilis, which is commonly associated with rotting hay or straw. 

 Assuming this to be the correct explanation, the other figures would show 

 that an enormously heavy dressing such as | lb. per foot does reduce the 

 number of .soil organisms, but to nothing like the extent that might be 

 expected, while ordinary dressings do not appear to produce anv distinct 

 action that can be separated from the normal range of fluctuation. 



The Rutherglen samples contained more mould spores than those from 

 Longerenong, possibly owing to their proximity to an orchard and vineyard 

 with deciduous trees. 



Field Test with Radio-Active Mineral as a Manure. 



Longerenong Plots. 



Four drill width strips were used for this experiment, each with a total 

 area oi approximately ^ of an acre. The wheat used was " Yandilla 

 King," and the manure and wheat were drilled in together. Plot i received 

 I cwt. of superphosphate per acre; plot 2 received | cwt. of superphos- 

 phate and I cwt. of finally divivded radio-active mineral per acre; plot 3 

 received \ cwt. of radio-active mineral per acre, and plot 4 was unmanured. 



No distinct sign was shown of any acceleration of germination by the 

 radio-active mineral at any of the early stages of growth. A month after 

 planting the plots i and 2 appeared to be about equal. Thev were much 

 ahead of plots 3 and 4, were a darker green, and had generally a more 

 healthy appearance. Two months after planting, the same differences 

 were noticeable. Plots i and 2 were about equal, and far ahead of plots 

 3 and 4, which were about equally backward, and a lighter green than plots 

 i_ and 2. Apparently, therefore, in quantities capable of practical applica- 

 tion, the radio-active mineral does not appreciably affect the earlv stages 

 of germination of wheat. Unfortunately, the season was a bad one for 

 wild oats, and these developed to such an extent on the plots as to spoil 

 them for harvesting. As far as could be judged, however, the plots i 

 and 2 remained ahead right up to har\esting, and tliese two plots with 

 equal amounts of superphosphate, and one with and one without radio- 

 active mineral were about equal. 



Rutherglen Plots. 

 A similar series of four plots was used in this case, each 4 yards 2 feet 

 broad (tw'o drill-widths), and approximately \ of an acre in area. Plot 

 I received 59 lbs. of superphosphate per acre; plot 2 received 59 lbs. of 

 superphosphate, and 59 lbs. of radio-active mineral per acre ; plot 3 re- 

 ceived I cwt. of radio-active mineral per acre; plot 4 was unmanured. In 

 addition, one small square plot received | lb. of radio-active mineral per 

 square foot as a top dressing. On the large plots the mineral and manure 

 were drilled in with the seed, using the single drill which deposits manure and 

 seed together. In this case, "Federation Wheat" was used, and was planted 

 on 5th May, 191 1. Six weeks afterwards, plots i and 2 were much ahead 

 of ]-lots 3 and 4, were greener, stooleB better, and were slightlv taller. 

 The small plot was best of all, Init weeds were thriving better on it than on 



