WOOTON AND STANDLEY FLORA OF NEW MEXICO. 61 



20. CENCHRUS L. Sand bur. 



Annuals or perennials with spreading or erect culms and few or many more or less 

 crowded "burs" in terminal spikes; spikelets 1-flowered, hermaphrodite, 1 to 4 

 together with an ovoid or globular involucre of rigid, more or less connate bristles 

 forming spiny burs or false capsules, these sessile or nearly so in simple terminal spikes 

 or racemes, falling with the spikelets; glumes awnless; grain free within the slightly 

 hardened lemma and palea. 



1. Cenchrus carolinianus Walt. Fl. Carol. 79. 1788. 



Type locality: Carolina. 



Range: Maine and Minnesota to Florida and New Mexico, and southward. 



New Mexico: Waste and cultivated ground at lower elevations throughout the 

 State; common. In sandy soil, in the Lower and Upper Sonoran zones. 



Sand burs are the most pernicious weeds of the State. They are often abundant 

 in cultivated ground, where, unless steps are taken to extenninate them, they spread 

 rapidly. In alfalfa fields they often become so numerous as to render the hay value- 

 less. The spines of the burs are extremely sharp and will pierce the uppers of shoes. 

 After they have entered one's flesh they usually break off when an attempt is made 

 to extract them. 



21. PHALARIS L. Canary grass. 



Annuals or perennials with flat leaves and densely flowered spikelike or capitate 

 inflorescence; spikelets 1-flowercd, strongly flattened laterally ; rachilla jointed above 

 the glumes; glumes awnless, equal, boat-shaped, usually -winged on the keel; lemmas 

 hard and shining in fruit, closely investing the grain and palea. 



KEY TO THE SPECIES. 



Glumes not winged; inflorescence a narrow panicle 1. P. arundinacca. 



Glumes winged; inflorescence spikeUke 2. P. caroliniana. 



1. Phalaris arundinacea L. Sp. PI. 55. 1753. Reed Canary grass. 

 Type locality: "Habitat in Europae subhumidie ad ripas lacuum." 



Range: British America to Nevada, New Mexico, and New Jersey; also in Europe 

 and Asia. 

 New Mexico: Chama (Standley 6806). Wet ground, in the Transition Zone. 



2. Phalaris caroliniana Walt. Fl. Carol. 74. 1788. Southern Canary grass. 

 Type locality: South Carolina. 



Range: California and South CaroUna to New Mexico and Florida. 

 New Mexico: Burro Mountains; Agricultural College. Moist ground. 



22. SAVASTANA Schrank. 



Fragi-ant perennials with flat leaves and usually rather small pyramidal terminal 

 panicles; spikelets 3-flowered, the terminal floret hermaphrodite, the others staminate; 

 rachilla jointed above the glumes; glumes nearly equal, about the length of the 

 spikelet, acute, smooth; lemmas about equaling the glumes, awule&s or short-awned; 

 stamens in the male florets 3, in the hermaphrodite floret 2; styles distinct, rather long; 

 grain free. 



1. Savastana odorata (L.) Scribn. Mem. Torrey Club 5: 34. 1894. Vanilla grass. 

 Eolcm odoratus L. Sp. PL 1048. 1753. 

 Hierochloe borealis Roem. & Schult. Syst. Veg. 2: 513. 1817. 

 Type locality: " Habitat in Europae frigidioris pascuis humentibus." 

 Range: British America to New Mexico, Wisconsin, and New Jersey. 



