GENERA OF GRASSES OF THE UNITED STATES. 63 



The giant reed is one of the largest of the herbaceous grasses, its 

 stem being as much as 20 feet tall. Ordinarily it grows in cultiva- 

 tion to a height of 6 to 10 feet. The rhizome is thick and knotty. 

 The blades are flat, 2 to 3 inches broad (smaller on the branches), 

 and distributed rather equally along the culm, the distichous ar- 

 rangement being conspicuous. The handsome feathery panicle is 1 

 to 2 feet long, the spikelets being about one-half inch long. In 

 the Southwest this is sometimes called by the Mexican name carrizo. 

 The stems of the giant reed are used for making clarionet and organ- 

 pipe reeds. 



Two large cultivated grasses or reeds allied to Arundo are Gyne- 

 rium and Cortaderia. 



Gynerium Humb. and Bonpl., PI. Aequin. 2: 105, pi. 115. 1809. 

 The single species described and figured is G. saccharoides Humb. 

 and Bonpl. This species, now called G. sagittatum (Aubl.) Beauv., 

 is a giant dioecious grass as much as 30 or 40 feet tall, with culms 

 clothed below with old sheaths from which the blades have fallen, 

 sharply serrulate blades, commonly 6 feet long and about 2 inches 

 wide (forming a great fan-shaped summit to the sterile culms), and 

 pale, plumy, densely flowered panicles 3 or more feet long, the main 

 axis erect, the branches drooping; spikelets several-flowered, the 

 pistillate with long-attenuate glumes and smaller long-silky lemmas, 

 the staminate with shorter glumes and glabrous lemmas. This grass, 

 found along streams in tropical America, is cultivated occasionally 

 in greenhouses under the name of uva grass. 



Cortaderia Stapf, Gard. Chron. III. 22: 396. 1897. Stapf in- 

 cludes five species in the genus, the first of which is C. argentea. 

 The genus is technically designated, on the page indicated in the 

 citation, but on a preceding page (p. 378) he says, "Taking Gyne- 

 rium argenteum as representative of the Cortaderas, . . .". Hence 

 Gynerium argenteum is selected as the type. This species, called 

 C. argentea (Nees) Stapf, is an erect dioecious perennial reed, grow- 

 ing in large bunches, with numerous long, narrow, basal blades, very 

 rough on the margins, and stout flowering culms 6 to 10 feet high, 

 with beautiful feathery, silvery white or pink panicles or plumes 1 to 

 3 feet long; spikelets 2 to 3 flowered, the pistillate silky with long 

 hairs, the staminate naked; glumes white and papery, long and 

 slender; lemmas bearing a long slender awn. This grass, called 

 pampas grass, is a native of Argentina. It is cultivated as a lawn 

 ornamental, being hardy in the warmer parts of the United States. 

 Pampas grass is cultivated commercially in southern California for 

 the plumes, which are used for decorative purposes. The plants 

 grow here to enormous size, as much as 20 feet in height. 



