THE SOBOHUM PLANT 283 



212. Technical description. — The plant varies in height 

 from about 4 feet (dwarf Milo) to 12 or 15 feet high in 

 some of the tropical forms. 



Panicle, or " head," varies in shape from the small, 

 compact " sumac " type, in which the rachis is almost 

 as long as the panicle, through the looser and more branch- 

 ing forms of the Collier type, in which the rachis is about 

 one-half that of the panicle, to the broom-corn type, in 

 which the rachis is only one-fifth the length of the branches. 



Seeds. — The shape of seed varies, from round in the 

 Kafir, Kowliang, and Shallu, to somewhat pear-shaped in 

 certain of the sweet sorghums, somewhat flattened in Milo, 

 and decidedly flat in the Durras. The seed coat of all 

 dark-colored varieties has a decidedly astringent taste, 

 due to the presence of tannin. The amount of tannin 

 seems to vary with the color, being greatest in the black- 

 seeded and dark red varieties, very little in yellow seeds, 

 and there being none in white seeds. The astringency 

 apparently has no ill effect except as it affects flavor, the 

 dark-seeded grain not being so desirable for stock food on 

 this account. 



Stems. — ■ Stems vary not only in height (from 4 to 15 

 feet), but also in relative thickness. The Amber variety 

 is slender, with stems less than 1 inch in diameter, while in 

 the Gooseneck variety the stems are 1 to 2 inches thick. 

 In slender-stemmed varieties the nodes are usually long, 

 about 12 inches; while in the stouter-stemmed varieties 

 the tendency is toward short nodes, as in the Sumac, 

 the average length being 8 or 9 inches. 



Juices. — Stems are designated as juicy or dry. The 

 actual water content of the green stems does not differ so 

 much in the two cases, the green stems being 80 to 90 per 

 cent water. In the juicy-stemmed varieties the juice is 



