PLANT GROWTH AT DIFFERENT STAGES 255 



357. Tassel. The tassel has some of the chemical 

 characteristics of the seed ; it is concentrated in nitrogen, 

 has less fiber, and an ash rich in phosphates. The flower 

 stalks and anthers yield an ash in composition like that of 

 the stems, while the ash of the pollen is nearly identical 

 with that of the matured grain. The pollen is par- 

 ticularly rich in nitrogen. One of the claims made for 

 detasseling corn, is to prevent loss of nitrogen and phos- 

 phoric acid through the pollen. It is estimated that the 

 nitrogen removed in the pollen amounts to from 5 to 

 jo pounds per acre. The fresh and dried silk (stigmas) 

 shows a decline in both nitrogen and phosphoric acid 

 after fertilization. 



358. Husk. The husk when first formed has all of the 

 materials for the development of the seed, and its compo- 

 sition at different stages of growth shows a gradual trans- 

 fer of its constituents to the ripening grain. When fully 

 mature, the husks are much poorer in ash and nitrogen 

 than the leaves or stems, but are not so poor as the cob. 

 The cob remains functionally active longer than any other 

 part of the plant, and is composed largely of cellulose and 

 pentose compounds, and contains but little protein or fat. 



359. Ripening Period. The corn plant, at first, absorbs 

 its mineral food and nitrogen at a very rapid rate. In fact, 

 there is but little mineral matter or nitrogen assimilated 

 during the last few weeks of growth. The last stage of 

 development is a period of rearrangement and transporta- 

 tion of the compounds from the leaves to the seed. The 

 composition of the different parts of the corn plant when 

 mature and of the ash is given in the following table : 



