35 



seeding to sow clover with the grain. If, however, it is designed to 

 remove two crops of grass, it can be seeded with a mixture of clover 

 and timothy. The grain crop will be harvested the first year; the 

 second season, the crop will be chiefly timothy; the third, it will be 

 timothy and clover; and at the end of the two or three years, which- 

 ever plan is followed, there will be in the field in the fall a good stand 

 of second-growth clover. Tliis should not be cut or fed, but should 

 be plowed under, and this is all the niore important if the piece has 

 not been treated with farm manure. This fall plowing should be 

 with lap furrow, and the following spring it should be thoroughly 

 worked with the disc and smoothing harrows, in order to get ready 

 for planting. 



It may in many situations be desirable to follow the grass crop 

 with corn, and then follow with potatoes. The same thorough prep- 

 aration will be of advantage to the corn crop. The land for the corn 

 should be liberally fertilized. Farm manure may be again used to 

 advantage at this point in the rotation. The corn crop must be over- 

 fed in every way, so that the land will be in a higher state of fertility 

 at the end than at the beginning of the season. If corn enters into 

 the rotation, fall plowing should be again practised, and the following 

 spring the land should be thoroughly worked. The best possible 

 seed bed should be prepared, so that the soil will be light and thoroughly 

 pulverized to a depth of 5 or even 6 inches. In a soil thus prepared 

 the planter will run easily. 



The Potato needs Abundant Plant Food. 



It is always profitable to fertilize a money crop liberally, and, 

 while a crop of 300 bushels of potatoes will remove from the soil 

 about 55 pounds of nitrogen, 25 pounds of phosphoric acid and 85 

 pounds of potash, it is probaloly wise to furnish the phosphoric acid 

 in considerable excess and the potash in fair excess. The plowed- 

 under clover and the fertility which has been accumulated can be 

 depended upon for part of the nitrogen. By many experiments it 

 has been found that the potato plant thrives best in a soil abun- 

 dantly supplied with all fertilizing elements. In the early stages of 

 growth nitrogen is particularly demanded, and hence a considerable 

 part of the nitrogen should be in a readily available water-soluble 

 form. This is necessary that it may be utilized by the plants early 

 in the season. Later when the tubers are forming, there is special 

 demand for phosphoric acid and potash. 



Selection of the Fertilizer. 



In the selection of a fertilizer, a farmer cannot be guided by the name 

 alone. There are all kinds of "potato " fertilizers upon the market, — 

 those carrjdng from 1 to 5 per cent nitrogen, from 5 to 10 per cent 

 phosphoric acid and from 2 to 12 per cent potash. In selecting the 

 fertilizer, something more than percentage composition must be 

 taken into account. 



At the present time a 4-6-10 fertilizer, carrying 4 per cent of 

 ammonia, which is equivalent to 3.3 per cent nitrogen, 6 per cent 

 available phosphoric acid and 10 per cent potash is a popular potato 

 fertilizer in Maine. Used at the rate of 1,500 pounds to the acre, 

 such a fertilizer would supply about 50 pounds of nitrogen, 90 povmds 

 available phosphoric acid and 150 i:)ounds of potash. Obviously 

 such a fertilizer when compared with the needs of the crop is out of 

 balance. As the results of field experiments with potatoes, it is prob- 



