37 



only half as strong plants compared with those that had received 

 3g. of nitrate of soda. With 6g. the difference was still greater. 



Maize does not send its roots deep, and requires, therefore, 

 much plant food near the surface. Farmyard dung and liquid 

 manure are very good. If intended for green fodder the large 

 varieties require per acre for a crop of 32,000 Ib. 60 Ib. of nitro- 

 gen, 32 Ib. of phosphoric acid, and 118 Ib. of potash, and for a 

 crop of 64,000 Ib. twice the before-mentioned quantities. The 

 smaller varieties require for 16,000 Ib. only 30 Ib. of nitrogen, 16 

 Ib. of phosphoric acid, and 59 Ib. of potash. To cultivate maize 

 for grain 48 Ib. of nitrogen, 22 Ib. of phosphoric acid, and 56 Ib. 

 of potash are withdrawn at a medium crop of 2,000 Ib. of grain and 

 2,760 Ib. of straw, &c. Twice the quantity of grain, with, how 

 ever, proportionately less straw, require 96 Ib. of nitrogen, but 

 somewhat less than twice the quantity of phosphoric acid and 

 potash as used for the medium crop. 



If your farmyard dung contains 48 Ib. of nitrogen, 14J Ib. of 

 phosphoric acid, and 32 Ib. of potash per manured acre, you mil 

 have to supplement for heavy crops with commercial manures ; and, 

 except nitrate of soda, they should be given long before the sowing 

 as regards muriate or potash and Thomas phosphate. If the soil 

 does not contain sufficient lime it is necessary to supply it, so as 

 to obtain the full benefit from the manures. 



Experiments made at Amherst, Mass., U.S., with maize for 

 fodder upon the same plots four years following each other show 

 that the soil required much potash, but not so much phosphoric acid. 

 Results of dried fodder per acre : 



Experiments made at the Kentucky Agricultural Station from 

 1889 to 1894 on the same land, and also at Lexington, in Ken- 

 tucky, U.S., resulted in loss where a superphosphate or nitrate of 

 soda, or both together, were applied. Sulphate of potash alone 

 gave always a good return and profit, and in most instances, when 

 added to the other plant foods, also a profit. The crops did almost, 

 without exception, decline from year to year, and in 1894, the 

 fifth crop in some instances was less than one-half compared with 

 that obtained in 1889. In the Western States generally from 35 

 to 80 bnshels are harvested per acre : 



