GRASSES OF IOWA. 



409 



mature^, yet there are exceptions, as it will be seen that the 

 first sample collected in April, having a height ©f 4 to 12 

 inche=, has only 2.84 per cent more of water than the sample 

 taken on July 20th and having a height of 48 to 49 inches. 



In considering the water free substance we find that the fat 

 present varies from 5.8i to 2.95 per cent and that the change is 

 not a constant one. The change in the amount of protein is 

 constant for the first six samples and changes from 23.16 per 

 cent to 7.81 per cent and the seventh sample having this 

 substance to the amcuntof 8.26 per cent, however in the results 

 for albuminoids we find that the decrease of this substance is 

 constant, changing from 17.99 per cent to 6.11 per cent. The 

 amount of crude fiber varies irregularly from 24.36 per cent in 

 the youngest sample to 37.72 in the third sample of May 28th. 

 The ash corstituent decreases with a regular charge while the 

 nitrogen free extract increases constantly, with oEe excepfon, 

 from 33.26 to 50.15 per cent, the exception being the third 

 sample with 30. 9 i per cent. The following analyses are added 

 for comparison: 



AIR DRY SUBSTANCE. 



Nimble Will {M. diffusa, Schreb.) is common in woods and 

 along roadsides in central and eastern Iowa. It affords some 

 picking but in meadows is a nuisance as it is extremely hard 

 to cut with a mower. 



Slough Grass (Spartina cynosdroides, Willd.), coarse peren- 

 nial, with erect simple stems from two to nine feet high, with 

 long pointed leaves and numerous erect or spreading spikes, 



1. S. D. BuU. Agrl. Exp. Sta. 40: 6t. 



2. BuU. Tenn. Agrl. Exp. Sta. 9: 90. 

 •Hay of grass. 



