GRASS FAMILY 
201 
rachis. the rachis breaking at the base of each joint, remaining attached 
as a pointed stipe to the spikelets above. Glumes narrow or setaceous, 1 
to 3-nerved, the nerves prominent, extending into one to several awns, 
these (when more than one) irregular in size, sometimes mere lateral 
appendages of the long central awn, sometimes equal, the glume being 
bifid. Lemmas firm, nearly terete, the apex slightly 2-toothed, 5-nerved, 
the nerves obscure, the central nerve extending into a long slender finally 
spreading awn, sometimes one or more of the lateral nerves also extending 
into short awns. Palea firm, nearly as long as the body of the lemma. 
(Greek sitos, grain for food.) 
1. S. jubatum J. G. Sm. Culms erect, 3 to 6 dm. high, rarely taller; 
spike erect, dense, 2.5 to 8 cm. long, thick and bushy from the numerous 
long awns.—Rocky or brushy hillsides and open dry woods and plains, 
widely scattered throughout cismontane Cal. Exceedingly variable in 
size, pubescence and length of awns. 
19. AVENA L. Oat 
Ours rather tall annuals. Panicles usually rather few-flowered, of 
usually large spikelets. Spikelets 2 to several-flowered, the rachilla 
bearded. Glumes about equal, membranous or papery, several-nerved, 
longer than the lower floret, usually exceeding the upper floret. Lem¬ 
mas indurate, except toward the summit, 5 to 9-nerved, bidentate at the 
apex, bearing a dorsal bent and twisted awn (this straight and reduced in 
A. sativa). (The classical Latin name.) 
Lemmas glabrous or nearly so...2. A. sativa. 
Lemmas pubescent with long usually brown hairs. 
Teeth of lemmas acuminate, not awned.1. A. fatua. 
Teeth of lemmas awned.3. A. barbata. 
1. A. fatua L. Wild Oat. Fig. 12. Culms 3 to 9 dm. high, erect, 
stout; panicle loose and open, the slender branches usually horizontally 
spreading; spikelets usually 3-flowered; glumes about 2.5 cm. long; 
rachilla and lower part of the shining lemma clothed with long stiff 
brownish hairs; florets readily falling from the glumes; lemma nerved 
above, about 2 cm. long, awn stout, geniculate, red-brown, twisted below, 
about 4 cm. long.—Fields and waste places, common; nat. from Eur. 
Var. glabrata Peterm. Differs in having nearly or quite glabrous 
lemmas.—With the species; nat. from Eur. 
2. A. sativa L. Cultivated Oat. Similar to no. 1 ; florets not read¬ 
ily separating from the glumes; spikelets usually 2-flowered; lemma gla¬ 
brous; awn straight, often wanting.—Commonly cultivated and occasion¬ 
ally escaped; native of Eur. Oats, the food of horses in England, is in 
Scotland the common food of the people (consult Dr. Samuel Johnson). 
In California oats are used as food by both horses and men. 
3. A. barbata Brot. Similar to no. 1 : spikelets somewhat smaller, 
mostly 2-flowered, the pedicels curved and capillary; lemma clothed with 
stiff red hairs, the acuminate teeth ending in fine awns 4 mm. long.— 
Fields and waste places; nat. from Eur. 
20. AMMOPHILA Host 
A tough rather coarse erect perennial, with hard scaly creeping 
rhizomes, long tough involute blades, and a pale dense spike-like panicle. 
