CHAPTER XXVII 



Factors Which Influence the Composition and 

 Feeding Value of Crops 



The main factors which influence the composition and 

 feeding value of crops are: (i) Seed, (2) soil, (3) cli- 

 mate, (4) stage of maturity, (5) method of preparation 

 as food, and (6) combination with other foods. 



360. Seed. The composition and individuality of the 

 seed influence the composition and feeding value of the 

 forage crop produced. Heavy-weight seeds are usually 

 more mature and contain a larger amount of reserve plant 

 food than those of light weight (see Section 338). Ex- 

 periments by Heilreigel show that the heavier the seed, 

 the more vigorous the young plant. Where there was 

 not an overabundance of plant food in the soil, the differ- 

 ence in vigor of plants was discernible even up to the time 

 of harvest. Experiments at the Illinois Station (Bull. 

 Nos. 53 and 55 ) show that by careful selection of seed 

 corn, the percentage amount of nitrogenous matter in the 

 grain may be increased from 0.5 to 1.25 per cent. Not 

 all of the cereals respond as does corn to the influence of 

 seed selection to produce variations in chemical compo- 

 sition. 



The care and storage which the seed receives prior to 

 planting also influences its vitality. When seed corn is 

 stored in a damp or poorly ventilated place, the excessive 

 amount of moisture results in injuring the vigor of the 

 germ. Seed wheat is often injured by being stored in 



