MANUAL OF THE GRASSES OF THE UNITED STATES 



743 



like, 20 to 60 cm. long, the slender 

 racemes drooping; spikelets about 3 

 mm. long, obscured in a basal tuft of 

 silky hairs 2 to 3 times as long as the 

 spikelet. % — Cultivated in the 

 Southern States, especially Louisiana, 

 for sugar and byproducts, and for 

 sirup, and also used for forage; com- 

 monly cultivated in tropical regions. 

 The sugarcanes cultivated in the 

 United States are derived chiefly 

 from four species and their hybrids. 

 In the Noble canes (S. officinarum, 

 chromosomes 40), described above, 

 the axis of inflorescence is without 

 long hairs. Chinese canes (S. sinensis 

 Roxb., chromosomes about 58 to 60), 

 with long hairs on the axis of inflor- 



escence, are cultivated chiefly for 

 sirup. Saccharwn barberi Jeswiet 

 (chromosomes about 45 or 46) from 

 northern India, differs from the last 

 in having narrower blades and more 

 slender canes. Varieties of this species 

 do not form an entirely homogeneous 

 group and may later be separated 

 into two or more species. The wild 

 cane of Asia (S. spontaneum L., 

 chromosomes 56), is used as a basis 

 for hybrids with other species. There 

 are numerous hybrids and varieties 

 of the species mentioned. 



Saccharum bengalense Retz. Munj. 

 Tall cane; blades very scabrous; panicle 70 

 to 80 cm. long, narrow, dense, silvery. Ql 

 — Sometimes cultivated for ornament. In- 

 dia. 



151. ERIANTHUS Michx. Plumegrass 



Spikelets all alike, in pairs along a slender axis, one sessile, the other pedicel- 

 late, the rachis disarticulating below the spikelets, the rachis joint and pedicel 

 falling attached to the sessile spikelet; glumes coriaceous, equal, usually 

 copiously clothed, at least at the base, with long silky spreading hairs; sterile 

 lemma hyaline; fertile lemma hyaline, the midnerve extending into a slender 

 awn; palea small, hyaline. Perennial reedlike grasses, with elongate flat blades 

 and terminal oblong, usually dense silky panicles. Type species, Erianthus 

 saccharoides (E. giganteus). Name from Greek erion, wool, and anthos, flower, 

 alluding to the woolly glumes. 



Spikelets naked, or nearly so, at base 1. E. strictus. 



Spikelets with a conspicuous tuft of hairs at base. 



Awn flat, spirally coiled at base, the upper portion more or less bent and flexuous or 

 loosely spiral. 

 Basal hairs nearly as long as the brownish spikelets; panicle not conspicuously hairy, 

 the main axis and branches visible; culms usually glabrous below panicle. 



2. E. CONTORTUS. 

 Basal hairs copious, about twice as long as the yellowish spikelets; panicle conspicu- 

 ously woolly, the hairs hiding the main axis and branches; culms villous below 



panicle..— 3. E. alopecuroides. 



Awn terete, or flattened at base, not coiled, the upper portion straight or slightly flexuous. 

 Basal hairs copious, much longer then the spikelet; panicle conspicuously woolly. 



6. E. GIGANTEUS. 



Basal hairs rather sparse, shorter than the spikelet; panicle not woolly. 



Uppermost blade not reduced, reaching the summit of the panicle; rachis joint and 



pedicel terete, sparsely long-pilose 4. E. brevibarbis. 



Uppermost blade usually much reduced; rachis joint and pedicel somewhat angled, 



sparsely short-pilose 5. E. coarctatus. 



1. Erianthus strictus Baldw. Nar- 

 row plumegrass. (Fig. 1129.) Culms 

 1 to 2 m. tall, relatively slender, 

 glabrous; nodes hirsute with stiff 

 erect deciduous hairs; foliage gla- 

 brous, the lower sheaths narrow, 

 crowded, the blades mostly 8 to 12 

 mm. wide; panicle 20 to 40 cm. long, 



strict, the branches closely appressed ; 

 spikelets brown, about 8 mm. long, 

 scabrous, nearly naked to sparsely 

 short-hairy at base; awn straight, 

 about 15 mm. long; rachis joint and 

 pedicel scabrous. % — Marshes 

 and wet places, Coastal Plain, Vir- 



