240 CROP GROWING AND CROP FEEDING 



legume crop rather than the sale crop should prevail. With a proper rota- 

 tion in which clover is brought in frequently on the land, and the home-made 

 manures are used on the corn crop, there will be a rapid increase in the humus 

 content in the soil, and there will be no need for the purchase of any nitro- 

 gen for the potato crop. For instance, suppose that the rotation is corn and 

 potatoes in same field, wheat after both, with clover sown on the wheat. One 

 year with clover and then the part that was in corn the previous round is put 

 in potatoes, and the part that was in potatoes goes in corn. Each have part 

 of the clover sod, but the corn is to get all the home-made manure, while the 

 potatoes are to have the artificial fertilizers, if any are needed. We say, if 

 any are needed, for we believe that it will be found most profitable to give the 

 clover the acid phosphate and potash it needs, and to depend on the clover 

 for the potatoes. Corn, as we have seen, also needs a good percentage of pot- 

 ash and nitrogen. But we have also seen that corn, as a field crop, never pays 

 the cost of purchased nitrogen, and I doubt if the potatoes will. But when 

 the clover the preceding year gets a liberal dressing of acid phosphate and 

 potash, it not only gives a heavier crop of forage, but makes the farm manure 

 richer in these things, and there will usually be no need for the purchase 

 of fertilizers for the potato or the corn crop. We would alternate the pota- 

 toes and corn every three years, so that all the land will get, during the rota- 

 tion, a dressing of the home-made manure ; and as this is detrimental to the 

 health of the potato crop if applied directly, it is not so when it has become 

 assimilated to the soil, and is simply organic matter like the clover that is 

 decaying around them. In the beginning of the improvement of a worn 

 soil it may be profitable to use some phosphoric acid and potash on the pota- 

 toes, but if the proposed rotation is carried out we believe that the fertiliza- 

 tion of the clover will be the better way to fertilize the potato crop. 



In this case there is no better application to the clover than 400 pounds 

 per acre of a mixture of equal parts of acid phosphate and kainit. For the 

 direct fertilization of the potato crop in the North, where the crop follows 

 clover, we would advise the mixture of 1,600 pounds of acid phosphate and 

 400 pounds of high grade sulphate of potash to make a ton, and would use 

 500 pounds of the mixture per acre; and put it all in the furrow under the 

 potatoes, since the potato plant does not spread its roots far. The potato 

 crop in the North depends to a great extent for its quality and starchiness 

 on the form in which the large percentage of potash is given it. Muriate 

 of potash is cheaper than the sulphate, and will make the larger increase in 

 the crop. But the quality will be inferior to that of the crop on which the 

 sulphate is used, as the chlorides seem to have a tendency to make the potato 

 more clammy. 



