292 EXPERIMENTAL STATIONS — REPORT FOR 1879. 



Again, it is well known that different crops find their nourish- 

 ment at different depths in the soil. Of the two crops we are 

 considering, the turnip, during its later growth, sends its roots 

 down deep into the soil, while barley lives more on the surface, 

 and when, in addition to these circumstances, we consider that 

 the wants of one crop are not quite the same as those of another, 

 we must be prepared to find considerable discrepancies in the 

 returns yielded by the same plots in different seasons, whether 

 the manuring has been continued or interrupted. 



The plots with dissolved phosphates scarcely show any 

 superiority over those with undissolved phosphates as regards 

 the yield of grain, though the straw of the latter has still the 

 advantage in every instance. Where nitrogenous manures have 

 been withheld, the yield of straw has been diminished more than 

 the yield of grain. Nitrate of soda has produced the same 

 amount of grain as sulphate of ammonia, but a much larger 

 return of straw. Sulphate of potash has produced a slightly 

 larger yield of grain, and slightly smaller yield of straw than the 

 muriate of potash. A considerable residue of the Peruvian guano 

 seems to have remained for the use of the barley crop, and the 

 fish guano plot has also improved its position, Ijut the produce 

 of straw in all the guano plots have not changed their relative 

 position. 



Regarding the j-j-^ ^^re plots, very little can be said. They 

 cannot be said to corroborate the results obtained on the rood 

 plots, and we must wait for the evidence of future crops before 

 we are able to pass an opinion upon their competency, to be con- 

 sidered checks upon the accuracy of the results obtained upon 

 the plots of which they are duplicates. 



Scheme of Experiments at the Experimental Agricultural 

 Stations of the Highland and Agricultural Society 

 OF Scotland, commenced May 1878. 



At each station there are 10 acres under experiment, divided 

 into 40 plots of 1 rood each. The cropping is a rotation of 

 turnips, barley, grass, and oats. The chief object of the experi- 

 ments is to determine the crop-producing value of the various 

 forms of the most important manures. The manures on each 

 plot contain 40 lbs. phosphoric acid, 30 lbs. potash, 10 lbs. 

 nitrogen, or half these quantities. 



