GRASSES OF IOWA. 165 



Sugar Producing Grasses. 

 ROBERT COMBS. 



The grasses containing sugar or sucro-e (C, H, 0^^) are 

 few, there being but three species that are known to contaia it 

 to any great extent. These species are corn or maize (Zea mays, 

 L.), sorghum {Androrogon sorghum, Brot.) and sugar cane {Sac- 

 charum officinarum, L). These plants all have stored up in 

 the pith cells of the internodes of the culms a greater or less 

 quan ity of sucrose, which quantify varies greatly according 

 to the age of the culm and the part used. 



Corn. — Experiments and analysis made by Prof. -Peter Col- 

 lier* and others show that, though at its maximum stage, 

 about August 20th, corn contains a goodly per cent (about 

 12 to 14 per cent) of sucrose, its period is of such short dura- 

 tion (about ten days or less) and the quantity before and af cer 

 the maximum is so small that it cannot be ecDnomically used as 

 a commercial source of sugar. The kernel, however, is used to 

 a great extent as a source of glucose, the latter being obtained 

 by the action of sulptiuric acid on the starch. 



Sorghum. — Certain varieties of this grass have been clearly 

 shown to contain sucrose, varying from 13 to 18 per cent, and 

 holding this content from four to six weeks, or even longer. 

 The United States Department of Ag iculturef has made almost 

 continuous experiments and iavestigadons aloag the line of 

 selecting and improving varieties, and in the matter of pro- 

 cesses of manufacturing sugar from sorghum from 1879 to 1893. 



Experiment stations were established in various parts of 

 the United States;):, and espacially in different parts of Kansas, 

 where at one tiaae (1889) there were nine. 



The plant was much improved in sugar content and much 

 improvement was made in the process of manufacture, but 

 since the removal of the sugar bounty (1893) the industry has 

 entirely collapsed. 



♦Report U. S. Dept. of Agrl. 188182: 452 pi. 14-16. 



i-Reps. U. S. Dept. Agrl. 1880-87: 



$Bull. U. 9. Dept. Agrl. Dlv. Chem 2: 6: 8: 14: 1": 18: 30; 26: 39: 34: 37: 40. 



