WEEDS 171 
at its base and bears on the side a blackish, twisted, and 
bent awn about an inch long. It is of light weight, shells 
easily, may lie in the ground many years and retain its 
vitality, and will germinate though buried to a depth of 
three or four inches. These attributes account for its 
rapid spread in a field after it once becomes established, and 
make it one of the worst weeds with which farmers have to 
contend. 
21. Quack Grass: Couch Grass. — This is one of the 
wheat grasses and it is hard for one who is not familiar with 
OLD WitcH GRASS Witp Oats Quack Grass 
it to distinguish it from the native species. The wheat 
grasses, including quack grass, are useful for hay and pas- 
ture. But quack grass cannot be confined to grass lands. 
It invades our cultivated fields and it is exceedingly difficult 
to kill on account of its long, jointed, running rootstocks. 
Of course there are other grasses, as June grass and Austrian 
brome grass, that have these underground stems, but none 
of them are half so hard to kill as this one. 
