418 THE HOME, FAKM AND BUSINESS CYCLOPEDIA. 



no means of remedying this condition is known save by the growth of 

 other crops for a series of years. 



Potash manures have generally a very beneficial effect upon leguminous 

 crops ; they fail, however, to cure clover sickness. Gypsum is also valuable, 

 though to a less extent. 



ROOT CROPS. All these crops contain a large amount both of nitrogen 

 and ash constituents ; among the latter potash greatly preponderates. Tur- 

 nips contain more sulphur than any other farm crop. 



The turnip and mangel crop differ in several respects. Turnips and 

 swedes draw their food chiefly from the surface soil. Their power of 

 taking up nitrogen from the soil is distinctly greater than that of the 

 cereal crops. Turnips are also well able to supply themselves with potash 

 when growing in a fertile soil, but they have singularly little power of 

 appropriating the combined phosphoric acid of the soil ; fresh applications 

 of phosphatic manures thus always produce a marked effect on this crop. 



Mangels have far deeper roots than turnips, and also a longer period of 

 growth. They have a great capacity for drawing food from the soil, in- 

 cluding both nitrogen, potash, and phosphoric acid. When removed off 

 the land they are probably the most exhaustive a crop a farmer can grow. 

 As mangels have not the same difficulty that turnips have of attacking 

 the combined phosphoric acid of the soil, phosphatic manures are, in their 

 case, of much less importance. Purely nitrogenous manures, as nitrate of 

 sodium, when applied alone to mangels, generally produce a great effect 

 on the crop ; this is not the case with turnips, which require phosphates 

 as well as nitrogen in their manure. 



As both turnips and mangels consume extremely large amounts of plant 

 food, a liberal general manuring with farmyard manure is in most cases 

 essential for the production of a full crop ; but the special characteristic 

 of the manure for turnips should be phosphatic, and of that for mangels 

 nitrogenous. 



Potatoes are surface feeders, and require a liberal general manuring to 

 ensure an abundant crop. 



As both root crops and potatoes require large supplies of potash, kainit 

 will be found of service on land naturally poor in that ingredient. It will 

 be chiefly required when the crops are raised with artificial manures only, 

 as farmyard manure will always supply a considerable amount of potash. 



It is worth noting in these times in our Provincial history that the 

 growth of forest timber is far less exhaustive to the soil than ordinary 

 farm culture. The demand on the soil becomes, however, considerably 

 greater if the trees are cut when young young timber and small branches 



