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7. G. grandis S. Watson (figure 22) Reed-meadow Grass 



Perennial. Swales and wet woods. Throughout the state; common 

 northward, infrequent southward. 



POA Meadow Grass; Bluegrass 



A large genus of annuals and tufted or rhizomatous perennials; flat 



blades ending in boat-shaped tips; spikelets small, often only 2-flowered; 



glumes keeled; lemmas keeled and distinctly nerved; awnless, usually with a 



tuft of cobwebby hairs at the base. 



Two species, Poa compressa and P. pratensis, are commonly planted in 



hayfields, but the latter being principally used for lawns. Poa annua is a 



pesty weed in gardens, lawns and golf courses and is able to produce seed 



even under regular mowing. 



A. Annual, lacking persistent old leaf bases of sheaths or offshoots 



P. annua 



A. Perennial, with persistent old leaf bases or sheaths or with offshoots 

 B. Plants with elongate rhizomes or geniculate basal offshoots 



C. Plants lacking or sparce cobwebby tuft of hairs on callus at 

 base of lemma; panicled mostly compact, spikelets crowded; 



culms flattened P. compressa 



C. Plants with conspicuous cobwebby tuft of hairs on callus at 

 base of lemma; panicles mostly open, the branches flexuous, 

 often spreading, with spikelets toward the tips; culms not 

 flattened 

 D. Culms arising from old dried leaves, new tufts developing 



at tips of stolons or offshoots; alpine P. alpigena 



D. Culms bearing ascending tufts of new leaves from basal 



sheaths; disturbed sites at low elevations P. pratensis 



B. Plants more or less tufted, without rhizomes or conspicuous 

 offshoots 

 E. Lemmas with 5 distinct nerves 



F. Ligules of upper leaves mostly 2-5 mm long; keel of 

 lemma scabrous to strongly pubescent P. trivialis 



F. Ligules of upper leaves mostly less than 2 mm; keel of 

 lemma glabrous, smooth P. saltuensis 



E. Lemmas with 3 distinct nerves, the intermediate ones obscure 



G. Plants low, mostly less than 4 cm; alpine or subalpine 

 H. Plant glaucous; panicles mostly erect and stiff 



P. glauca 



H. Plant green; panicles often nodding with thin 



flexuous branches P. fernaldiana 



G. Plants mostly taller than 5 cm, up to L5 m; lower 

 elevations 

 L Margins of lemmas pubescent 



J. Ligules 1 mm or less long; panicles open, 5-15 cm 

 long, branches spreading, lax P. nemoralis 



