How the Plant Groivs. 



9 



the name of the feeding stuff, followed by the number of analyses 

 from which the average composition is derived. The remaining col- 

 umns give the average percentage composition of the several nu- 

 trients. 



Sample table showing the percentage composition of plants. 

 (For full table consult Table I of Appendix.) 



9. Water. To determine the amount of water in a fodder the 

 chemist places a small quantity of the material, finely divided, in a 

 dish and ascertains its weight. It is then dried in an oven at a tem- 

 perature of 212 F. for several hours and again weighed. The dif- 

 ference between the first and last weights represents the amount of 

 water in the sample. From the third column of the table we learn 

 that fresh pasture grass is about 80 per ct. or four-fifths water, 

 while dent corn contains 10.6 per ct. and red clover hay 15.3 per ct. 

 of water. 



10. Ash. The chemist next burns the sample, weighing as be- 

 fore, to ascertain its ash or mineral content. From the next col- 

 umn of the table we learn that 100 Ibs. of fresh pasture grass has 2 

 Ibs. of ash, which is about twice that in mangels. Red clover hay 

 has 6.2 Ibs. of ash per 100 Ibs. This large amount is due to the ac- 

 cumulation of mineral matter in the clover leaves during growth, to 

 earthy matter washed upon the growing plants by rain, and to dust 

 settling on the hay before it is housed. The foreign material is not 

 really plant ash, but of necessity is reported as such. The ash and 

 water of plants constitute the so-called inorganic matter; the other 

 components combined are termed the organic matter. 



11. Crude protein. The process of determining the nitrogenous 

 constituents of feeding stuffs is too complicated for presentation 

 here. Suffice it to say that tjxe nitrogen content is found and the 

 result multiplied by 6.25 to give the crude protein, since about 16 



