MANUAL OF THE GRASSES OF THE UNITED STATES 721 



short, swollen; sheaths greatly overlapping, the lower usually falling 

 from the culms; blades elongate, mostly 4 to 6 cm wide, with a very 

 thick midrib; panicle plumelike, 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; commonly 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. offici- 

 narum, chromosomes 40), described above, the axis of inflorescence 

 is without long hairs. Chinese canes (S. sinensis Roxb., chromosomes 

 about 58-60), with long hairs on the axis of inflorescence, are culti- 

 vated chiefly for sirup. Saccharum barberi Jeswiet (chromosomes 

 about 45-46) 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 sepa- 

 rated 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 ciliare Anderss. Tall cane; blades very scabrous; panicle 70 to 

 80 cm long, narrow, dense, silvery. 2/ — Sometimes cultivated for ornament. 

 India. 



143. ERIANTHUS Michx. Plumegrass 



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

 pedicellate, the rachis disarticulating below the spikelets, the rachis 

 joint and pedicel falling attached to the sessile spikelet; glumes coria- 

 ceous, 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 sac- 

 charides. Name from Greek erion, wool, and anthos, flower, alluding 

 to the woolly glumes. 



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



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 about 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 

 conspicuously 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 rather sparse, shorter than the spikelet 4. E. brevibarbis. 



Basal hairs copious, longer than the spikelet 5. E. giganteus. 



1. Erianthus strictus Baldw. Narrow plumegrass. (Fig. 1607.) 

 Culms 1 to 2 m tall, relatively slender, glabrous; nodes hirsute with 

 stiff erect deciduous hairs ; foliage glabrous, 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 



