HOW TO KNOW THE GRASSES 



40b. Rachilla not prolonged; weak, sprawling weedy grass of disturbed 

 soil, lawns, etc. Fig, 225. 



NIMBLE WILL MuWenbergia schreberi GmeL 



Perennial. The culms in early season 

 are quite erect, but by flowering time they 

 become much-branched and sprawl on the 

 ground, the lower nodes often rooting. The 

 erect portions of the culms are 10 — 30 cm. 

 long. Leaf blades usually 2 — 4 mm. wide; 

 foHage glabrous; panicles borne at the tips 

 of the culms and from leaf axils, slender 

 and weak, 5 — 15 cm. long. The glumes 

 are vanishingly small, the first sometimes 

 entirely lacking and the second only a few 

 tenths of a miUimeter long. Florets cylin- 

 drical, about 2 mm. long, hairy on the 

 callus; awn 2 — 5 mm. long, very slender. 

 Nimble Will may become a weed in shaded 

 lawns and shrubbery borders, but it does 

 not seem very aggressive. It also is found 

 growing in woods and thickets, roadsides 

 and city streets, old fields, and meadows. 

 August — October, rarely blooming in June 

 or July. 



Figure 225 



41a. Lemma bearing an awn; nerves of lemma 3 or 5 



42 



41b. Lemma awnless; nerves 1. 3, or 5 



51 



42a. Plants producing elongated rhizomes 43 



42b. Plants lacking rhizomes (old tufts sometimes stooling out) 47 



43a. Panicles slender, with short ascending branches; spikelets owned 

 or awnless, on short pedicels 44 



120 



