EXPERIMENTAL STATIONS — EEPORT FOE 1880. 



357 



It will be seen that the yield of grain in the various plots 

 differs very little. It is only in the produce of straw that any 

 marked differences are decernible, and these correspond for the 

 most part with the differences observed in the previous turnip 

 crop. This is shown very clearly on a comparison of the 

 undissolved phosphate with the dissolved phosphate plots, where 

 the difference in favour of the latter, as regards straw, is still 

 about 15 j)er cent., but as regards grain it is almost nil. 



Undissolved Phosphates. 



On comparing the odd plots 11 and 12, 17 and 18, 21 and 22, 

 it will be seen tliat in this station also tlie want of nitrogen is 

 felt more than the want of ])hosphoric acid or potash ; and it is 

 evident that the use of a larger amount of nitrogenous manure 

 would result in the obtaining of much larger crops. The amount 

 per acre might even be doubled, not only with advantage to tlie 

 crop, but also to the experiments, for the use which the plant is 

 able to make of the mineral food presented to it in the soil is 

 limited by the amount of nitrogenous food which it can obtain. 



