SUPPLEMENT. 



45 



sugar-beet industry has reference to two important objects, 

 namely, an adequate supply of food to each crop and the pro- 

 duction of the largest possible amount of animal manure. A 

 fair crop of beet roots is of course more exhausting to the soil, 

 as far as phosphoric acid, and particularly potassa, is concerned, 

 than most of our farm plants ; a judicious system of rotation 

 divides that effect over several years, and thus enables the 

 farmer to draw more efficiently on the natural resources of 

 the soil, and so avoid a direct outlay of money. The follow- 

 ing succession of crops is considered very satisfactory, viz. : 

 green fodder, wheat, sugar-beets, and, finally, a summer grain 

 crop ; or barley, sugar-beets, barley, green fodder, wheat, 

 sugar-beets ; and these are economical as far as manure is con- 

 cerned. Two thousand three hundred pounds of hay, or its full 

 equivalent in fodder value, are considered sufficient to replace 

 the constituents which a fair beet sugar crop abstracts per acre 

 in excess of what the refuse material resulting from such crop 

 in the course of beet sugar manufacture will compensate for. 

 The amount of refuse material fit for manuring purposes is 

 counted per acre equal to 4,700 pounds. T. T. Fiihling's 

 figures on this question are of great interest as they come from 

 a practical sugar-beet cultivator, whose opinion is regarded as 

 of great importance. They refer to pounds per acre. 



* Substances abstracted by a full sugar-beet crop, 

 t Substances returned in the manure obtained from sugar-beets. 

 t Amount of substances not replaced by that manure. 



§ Amount of substances abstracted per acre during a four years' rotation as detailed, 

 tl Amount of substances restored to the soil by the manure resulting from the feeding 

 of 2,300 pounds of hay. 



