40 



THE FEEDING OF ANIMALS 



ways: in organic combinations and as the inorganic salts 

 of plant solutions, crystals and incrustations. Outside 

 of phosphorus and sulfur, little is known of the relations 

 to plant structure of the important ash elements, such as 

 potassium, calcium, and magnesium. Their place as 

 bases in organic structures is not fully understood. 



51. Variations of plant ash. The ash from different 

 plants and feeding-stuffs is by no means uniform in com- 

 position and quantity, even in the same species or class 

 of materials, although with the grains there is some degree 

 of uniformity in this respect. Certain factors cause varia- 

 tions, such as species, stage of growth, fertility, the part 

 of the plant, and changes due to manufacturing processes. 



52. Variations of ash due to species. Different species 

 of plants, and consequently different feeding-stuffs, 

 are greatly unlike in their content of mineral matter. 

 The figures of Table XI illustrate this fact: 



TABLE XI 



