458 



Journal of Agriculture, Victoria. [10 Aug., 1916. 



It was found as an average of a number of tests that the root growth 

 was equal to 22 per cent, of the overhead development. The average 

 composition of the roots was — nitrogen, 2.1 per cent. ; phosphoric acid, 

 .5 per cent.; potash, 1.1 per cent.; and lime, 1.2 per cent. Applying 

 these results to the unmanured plot mentioned above, the total weight 

 of roots formed during the two years would be equal to 47 cwt. of dry 

 roots and root hairs per acre. Hence, there would remain in the roots 

 of this crop — 



Nitrogen, 69.2 lbs. 



Phosphoric acid. 16.2 lbs. 



Potash, 36.0 lbs. 



Lime, 39.6 lbs. 

 These figures will give some idea of the enormous foraging power 

 of the root system of lucerne. 



Fig. 6. — Curing Hay on Lucerne Manurial Plots, State Research 

 Farm, Werribee. 



The Wonderful Foraging Power of Lucerne. 



In other words, during the space of two years the unmanured plot 

 of lucerne took from the soil enough phosphoric acid to supply the 

 needs of five 30-bushel wheat crops, and left behind in its roots more 

 than enough of the same ingredient to bring a 30-bushel crop to 

 maturity. It took from the soil in two years enough nitrogen to sup- 

 ply nine 30-bushel wheat crops, and it left behind in its roots enough 

 nitrogen for more than tiro such crops. 



Finally it removed potash in two years sufficient to supply thirty-six 

 wheat crops, and at the same time there was enough left in its roots 

 to furnish potash for four wheat crops. 



Time and Manner of Applying Fertilisers. 



The most suitable time to apply top dressings to established lucerne 

 is in August, just before the soil temperatures begin to rise. The 

 lucerne may be grazed with sheep towards the end of July, or early in 

 August, if the soil is dry enough to carry them without puddling the 



