172 BOARD OF AGRICULTURE. [Pub. Doc. 



clover the largest crop of hay in any year from 1894 to 1900 

 inclusive amounted to but 2.12 tons per acre, two crops 

 amounted to less than 1 ton and several others scarcely ex- 

 ceeded a ton. At the outset the soil was too acid to permit 

 of the growth of timothy, and at first red-top seed was 

 omitted in the rotation including the clover, which facts 

 help to explain many of the poor yields. In 1899 a special 

 top-dressing experiment was begun in another connection, to 

 see how much nitrate of soda was required, in the presence 

 of lime and an abundance of asshnilable potash and phos- 

 phoric acid, to produce 4 tons of hay per acre, in addition 

 to the nitrate naturally formed in the soil. As a result, 

 it has been found that 350 pounds of nitrate of soda per 

 acre arc probably sufficient to produce 4 tons of field-cured 

 hay annually under the conditions named, and the average 

 yield of field-cured hay per annum in the experiment re- 

 ferred to has been maintained at over 4 tons per acre for five 

 consecutive years. 



Still other experiments have shown that the amount of 

 dissolved bone-black, though supplying phosphoric acid 

 probably in excess of that removed by the crop, was yet 

 probably insufficient, in view of the changes in its assimila- 

 bility which takes place in the soil. It has also been shown 

 that 120 pounds of muriate of i)otash were much too little to 

 produce a maximum crop, even when aided by the potash 

 regularly freed from our granitic soil. In other Avords, it 

 has been abundantly demonstrated that the most faulty featiu'e 

 of the five-year rotations, as originally planned, was in the 

 formula for top-dressing the grass land. In the light of all 

 the recent results to date, it seems probable that the greatest 

 profit obtainable might have resulted had a formula essen- 

 tially as follows been employed for grass, viz. : — 



ProjJosed Substitute Formula for To2)-dressmg Orass Land. 



Pounds per Acre. 



Nitrate of soda, ...... 350 



Acid phosphate, ...... 500-600 



Muriate of potash,* 200-250 



* It is possible that this coukl occasionally be replaced profitably by twice the 

 amount of double sulfate of potash and magnesia, ixvrticularly in the rotation 

 where clover is grown. 



