A26 ItLtinois NATURAL History SuRVEY BULLETIN 
food for baldpates and gadwalls. It 
furnishes little seed, but ducks make ex- 
tensive use of the leaves and stems. 
Teal grass, Eragrostis hypnoides, has 
a status that cannot be judged by any 
index figures’ derived from use and 
abundance data recorded for this spe- 
cies, tables 3,4,5 and6. This is evident 
from the fact that in 1938 and 1939 it 
formed respectively 3.16 and 1.54 per 
cent of the food taken, while only a few 
small patches of plants were seen on ex- 
Vol. 22, Art. 5 
tensive mud flats around several lakes. 
In all probability, ducks in those years 
obtained seeds deposited by growths of 
previous seasons. ‘This small, procum- 
bent plant in 1940 was overgrown by 
pigweeds, millets and smartweeds to 
such an extent that accurate mapping 
of the areas covered by the numerous 
scattered patches was impossible. 
From its relatively high use and ap- 
parently low occurrence, we believe that 
teal grass ranks above duck potato in 
Fig. 10.—Marsh smartweed (Polygonum Muhlenbergii), one of the few smartweeds that 
grows in water, can readily be identified by its bright pink blossoms. 
It is not so valuable a duck 
food plant as largeseed or nodding smartweeds because it does not produce so much seed. 
