THE FEEDING STUFFS 577 



ture of energy in digestion (770). Not only does coarse, woody 

 forage contain less digestible matter, but what it does contain 

 is less valuable to the animal, pound for pound, than that de- 

 rived from forage of a better quality. 



682. The legumes the clovers, alfalfa, peas, beans, vetches, 

 and the like constitute a source of forage second only to 

 the grasses in importance, while their value as renovating 

 crops gives them a peculiar position in agriculture. Broadly 

 speaking, leguminous forage may be said to differ from that 

 of the grasses in two main points. First, under like condi- 

 tions it is notably richer in proteins than the latter. Second, 

 there is a more marked difference between the physical proper- 

 ties of the stems and the leaves in the legumes, the rather coarse 

 stems increasing relatively to the leaves with advancing ma- 

 turity. Hay from somewhat mature legumes is therefore likely 

 to be bulky, to have a higher percentage of crude fiber than 

 grass hay, and relatively to be less digestible. For the same 

 reason it is more subject to mechanical losses in curing, which 

 likewise lower its quality. For all these reasons, the compo- 

 sition and digestibility of leguminous forage show an even 

 greater range than those of the grasses, and the importance of 

 timely cutting is still more marked. In brief, the influences 

 which affect the composition and digestibility of the grasses 

 affect those of the legumes in substantially the same way but 

 to an even greater extent. 



683. Straw consists of the vegetative organs of the plant 

 after the removal of the ripe or nearly ripe seeds. Since the 

 ripening of the seed consists largely in the transfer to it of sol- 

 uble materials from the leaves and stems, it follows that the 

 straw will be poor in digestible materials in proportion to the 

 extent of seed formation and the degree to which the seeds 

 ripen. Furthermore, those parts of the plant most distant from 

 the seed are found to be most completely exhausted of food 

 material. The straw of the common small grains is relatively 

 very poor in proteins and fat, while still containing not incon- 

 siderable amounts of digestible carbohydrates and related sub- 

 stances. Its tough, woody character, however, as indicated by 

 its high percentage of crude fiber, points to a relatively large 

 expenditure of energy in its digestion, and its real nutritive 

 value is therefore low. Wheat and rye straw stand at the 



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