HOW TO KNOW THE GRASSES 



lb. Plants with erect tall culms, 1 — 3 m. tall; leai blades 1—4 cm. 

 wide 2 



2a. Pistillate spikelets all at the upper tip of the panicle, forming an 

 erect brush; awns of the pistillate spikelets several times as long 

 as the lemma; staminate spikelets all on spreading lower branches 

 of the panicle. Fig. 280. 



WILD RICE. Zizania aquatica L. 



Figure 280 



Annual; culms stout, 2 — 3 m. or more 

 tall; panicles 30 — 50 cm, long, open and 

 pyramidal. The spikelets consist of single 

 florets, which disarticulate from minute 

 cup-like structures which are the vestiges 

 of glumes. Wild rice was an important 

 food plant for the American Indians, who 

 threshed the standing plants into canoes. 

 It still furnishes some food for human be- 

 ings and the grain can occasionally be 

 purchased in stores. In nature, wild rice 

 is an important producer of food for water 

 fowl. Shallow water, ditches, ponds, 

 streams and marshes. July — September. 



2b. Pistillate spikelets intermixed with the staminate ones on the same 

 branches; awns of pistillate spikelets not longer than the lemma. 

 Fig. 281. 



SOUTHERN WILD RICE Zizaniopsis miliacea (Michx.) Doell. 



Perennial; plants 1 — 3 m. tall or taller, the 

 culms arising from stout rhizomes; panicles 

 nodding, 30 — 50 cm, long. Leaves very sca- 

 brous on the margins. The spikelets consist 

 of single florets, which disarticulate from the 

 vestigial glumes, as in the previous species. 

 The staminate ones have 6 stamens instead 

 of the usual 3. Marshes and along streams. 

 May — June. 



Figure 281 



148 



