In general appearance black grama somewhat resembles blue 

 grama (Boubeloua gmcilis). Blak grama has an above-ground 

 stoloniferous method of revegetation, a greater number (usually 

 4 or 5) of flaglike spikes in the flower head, conspicuous tufts of 

 whitish, woolly hair at the bases of the loosely arranged spikelets, 

 and jointed, branched, and densely woolly steins. Such characters 

 contrast strongly with blue grama's underground rootstock method 

 of spreading (which in the north results in a rough sod formation), 

 its fewer (usually 1 to 3), erect (in age strongly curved) spikes, 

 crowded spikelets (as many as 80 in some spikes), and its un- 

 branched stems (except occasionally at base), and serve to distin- 

 guish these two very important gramas. 



