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MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



36. ORCUTTIA Vasey 



Spikelets several-flowered, the upper florets reduced, the rachilla con- 

 tinuous, the spikelets persistent even after maturity; glumes nearly equal, 

 shorter than the lemmas, broad, irregularly 2- to o-toothed, many-nerved, 

 the nerves extending into the teeth; lemmas firm, prominently 13- to 15- 

 nerved, the broad summit toothed; palea broad, as long as the lemma. Low 

 annuals with short culm blades, solitary spikes or spikelike racemes, the sub- 

 sessile spikelets relatively large, the upper aggregate, the lower more or 

 less remote. With the exception of 0. greenei, the young plants produce 

 elongate juvenile leaves before the development of the culms. Type species, 

 Orcuttia californica. Named for C. R. Orcutt. 



Lemmas with 7 to 11 very short teeth 1. O. greenei. 



Lemmas with 5 relatively long acuminate or awn-tipped teeth. 



Racemes 2 to 5 cm. long, often capitate, the spikelets usually crowded toward the summit, 

 remote toward the base; teeth of lemma unequal, the middle longer than the lateral 



ones; nerves of lemma relatively faint - 2. O. califorxica. 



Racemes 5 to 10 cm. long, narrow, not capitate, the spikelets rather evenly distributed 



(the lower distant in 0. tenuis); teeth of lemma equal; nerves of lemma prominent. 



Blades 1 to 2 mm. wide; spikelets mostly 2- to 10-flowered, glabrous.... 3. O. tenuis. 



Blades 2 to 6 mm. wide; spikelets mostly 10- to 40-flowered, pilose 4. O. pilosa. 



1. Orcuttia greenei Vasey. (Fig. 

 295.) Culms 15 to 20 cm. tall, sub- 

 erect; blades 2 to 3 cm. long, sub- 

 involute; raceme 3 to 7 cm. long, 

 pale; spikelets 10 to 15 mm. long, 

 loosely papillose-pilose; glumes 4 to 

 5 mm. long; lemmas 6 mm. long, the 

 obtuse or truncate tip spreading, 7- 

 to 11-toothed, the teeth mucronate 

 but not awned. O — Moist open 

 ground, Sacramento and San Joaquin 

 Valleys, Butte and San Joaquin 

 Counties, southeast to Tulare County, 

 Calif. At maturity foliage and spike- 

 lets minutely viscid-glandular. 



2. Orcuttia californica Vasey. (Fig. 

 296.) Culms 5 to 15 cm. long, spread- 

 ing with ascending ends, forming 

 little mats; foliage thin, pilose, the 

 sheaths loose, the blades 2 to 4 cm. 

 long; raceme loose below, dense or 

 subcapitate at the summit; spikelets 

 8 to 12 mm. long, densely to sparsely 

 pilose; glumes sharply toothed; lem- 

 mas about 6 mm. long, deeply cleft 

 into 5 awn-tipped teeth. The whole 

 plant at maturity more or less viscid- 

 glandular. O — Drying mud flats, 

 near Murrietta, Riverside County, 

 Calif.; Baja California. 



Orcuttia californica var. in- 

 aequalis (Hoover) Hoover. Resem- 

 bling the species, but differing in having 

 usually shorter capitate inflorescences 



Figure 293. — Triplasis americana. Panicle, X 1 ; 

 floret, X 5. (Curtiss 5570, Fla.) 



and unequally toothed lemmas; culms 

 ascending or prostrate. Sacramento 

 and San Joaquin Valleys, Sacramento 

 to Tulare County, Calif. 



Orcuttia californica var. vis- 

 cida Hoover. Plants very viscid; 

 teeth of lemma awned, giving the 

 capitate inflorescence a distinctly 

 bristly appearance. Near the Sierra 

 Nevada foothills, Sacramento County, 

 Calif. 



3. Orcuttia tenuis Hitchc. (Fig. 

 297.) Culms in small tufts, slender, 



