GRASSES OF IOWA. 



413 



WATER FREE SUBSTANCE. 



Sample 1. 

 Sample 2. 

 Sample 3. 

 Sample 4. 

 Samp'e 5. 

 Sample 6. 

 Sample 7. 



40 02 

 44.09 

 43 54 

 42.33 

 45.53 

 47.17 

 43.57 



It will be noticed that the above results show that the water 

 content gradually decreases with one exception as the grass 

 matures. The fat in the water free substance is largest in the 

 youngest sample and varies in the oth' rs. The percentage of 

 protein gradually decreases from 15 34 to 5.52 per cent in the 

 first six samples, and then we find 7.29 per cent in the last 

 sample. In the albuminoids we find that the amounts are not 

 constant in their changes, the second sample having 10.17 per 

 cent and the fifth sample 4.24 per cent. In the fiber there is a 

 constant increase as the plant becomes matured. The nitro- 

 gen free extract increases Jrom 40 02 per cent in the first 

 sample, and increases to 47.17 per cent in the sixth sample. 

 The amount of ash varies from 6 71 per cent to 4.90, and the 

 changes are very irregular. The following analyses are added 

 for comparison: 



NATURAL CONDITION. 



Iowa (1). 

 Cut Aug 27, in bloom, 



he'ght, 60 inches 



Cut June 1, no heads, £0 



inches 



Cut Aug. 27 



S. D., (2) July 10, 1891.... 



O *s 



24 71 



44 89 

 53.19 

 50.91 



Needle Grass, or porcup'ne grass (Stipa spartea, Trin.) is 

 widely distributed in this state occurring on dry gravelly 

 knolls. The leaves are long and wiry. It grows in bunches 



* These give the water which is found in the natural condition, while the other 

 percentages of these analyses are for the water free substances. 



+ The amount of water is for air dried material; the other results for the water free 

 substance. 



1. Bull. la. Agrl. Exp. Sta. 11: 456, 478. 



2. Bull. S. D. Exp. Sta. 40: 94, 1894. 



