COMPOSITION OF PLANTS. 



19 



To the practical farmer it is, therefore, of the greatest importance to recollect this 

 principle, that the fiber or valuable part of the Flax is not formed by exhaustion of the soil, 

 but the materials which the Flax plant takes out of the land are all found in the steep- 

 water and the chaff ; and that if these be returned to the earth they will restore its fertility, 

 and that thus the Flax crop may be rendered one of the least injurious to the ground, and 

 most remunerative to the farmer." 



COMPOSITION OF PLANTS. 



Following are analyses, made by Sprengel and Sir Robert Kane, of both Flax seed and 

 the entire Flax plant, showing the relative quantities of inorganic matter contained in 100 

 parts of their ashes : 



Assuming the yield of an acre to be two tons of straw and ten bushels of seed, each 

 bushel weighing 56 Ibs., the quantity of inorganic matter abstracted from the soil will be : 

 In the Seed ............................................. 13^ Ibs. 



In the Straw ............................................ 65*4; Ibs. 



Total 



Ibs. 



Prof. Hodges, Queen's College, Belfast, who has devoted much time to study of the Flax 

 plant, writes that "it is an exhausting crop (like every other plant that is cultivated for food, 

 "or for its utility in the manufacture of clothing, or, indeed, iike every weed that springs up 

 " along the highway), in that it takes certain matters from the soil. When only part of the 

 " plant, like wheat, for instance, is sent to market, it is clear that only a part of the matters 

 " of the soil is lost to the farm, and therefore its exhaustion is delayed." 



But he claims that Flax is not as exhaustive as some other crops, and gives the following 

 table showing the amount of phosphoric acid and alkalies contained in 100 parts of the ash 

 of several plants : 



Phosphoric Acid. Potash and Soda. 



Flax, - 

 Wheat Straw, 

 Oat Straw, - 

 Bean Straw. 

 Red Clover, - 

 Cabbage, - 

 Potato Stalks, 

 Turnip Tops, 



7 



3 - 

 3 

 7 - 



8 



12 - 



7 

 9 - 



12 

 13 



9 



55 



:/- 

 32 



44 

 34 



According to Dr. Lyon Playfair, a crop of wheat, at the rate of 25 bushels of grain 

 and 3000 Ibs. of straw, will take from the land 175 Ibs. of inorganic matter ; beans, 231 Ibs. ; 



