TABLE OF CHEMICAL CHANGES. 



143 



Time of cutting corn for the silo.^ — In order to determine at 

 what stage of growth corn had better be cut when intended for the 

 silo, it is necessary to ascertain the amount of food materials 

 which the corn plant contains at the different stages, and the 

 proportion of different ingredients at each stage. Prom careful 

 and exhaustive studies of the changes occurring in the composition 

 of the corn plant, which have been conducted both in this country 

 and abroad, we know that as com approaches maturity the nitro- 

 genous or flesh-forming substances decrease in proportion to the 

 other components, while the non-nitrogenous components, especi- 

 ally starch (see Glossary), increase very markedly; this Increase 

 continues until the crop is nearly mature, so long as the leaves 

 are still green. Several experiment stations have made investi- 

 gations in regard to this point. As an illustration we give in 

 Table X data obtained by Pro'f. Ladd, in an investigation in which 

 fodder com was cut and analyzed at five different stages of 

 growth, from full lasseling to maturity. 



Table X. — Chemical Changes in the Corn Crop. 



YIELD PER ACRE 



TaB- 

 seled. 

 July 30 



Bilked. 

 Aug: 9 



Milk. 

 Aug. 21 



Glazed. 

 Sept. 7 



Ripe. 

 S6pt. 23 



Gross Weight 



Water in the Crop 



Dry Matter 



Ash 



Crude Protein 



Fiber 



Nitrogen -free Extract 



(starch, sugar, etc.) . 

 Crude Fat 



Pounds. 



118045 

 . 116426 

 .| 2619 

 .| 138.9 

 . I 239.8 

 .1 .514.2 



.| 653.9 

 .| 72.2 



Pounds. 

 25745 

 22666 

 3078 

 201.3 

 436.8 

 872.9 



1399.5 

 167.8 



, Pounds, 



32600 

 27957 

 4643 

 232.2 

 478.7 

 1262.0 



2441.3 

 228.9 



PoundB. 



32295 

 25093 

 7202 

 502.5 

 643.9 

 2755.9 



3239.8 

 260.0 



Pounds. 



28460 

 20542 

 7918 

 364.2 

 677.8 

 1734.0 



4827.6 

 314.3 



The data given above show how rapidly the yield of food 

 materials Increases with the advancing age of the com, and also 

 that increase during the later stages of growth comes largely on 

 the nitrogen-fed extract (starch, sugar, etc.). 



