SORGHUM, seegilm, an annual cane-like plant (Holcus sorghum), resembling Indian corn in general appearance and habit of growth. The sorghums are without ears, and are dis tinguished by heavy heads of small seeds which terminate the stalk. (See GRASSES). The cultivated varieties are usually treated as a distinct species by botanists, but some prefer to consider them as derived from a wild species, Holcus halepensis. The sorghums have been known from the remotest periods of history, and the cultivation of sorghum probably had its origin in Africa, where a variety called durra is grown over the whole continent, and is put to a variety of uses • the negroes chew the stem for the sugar, and make alcoholic drinks from the grain. Varieties of sorghum were known in China from a very remote period. The first sweet sorghum seed to reach the United States came from that country; in 1855, and in 1856 from South Africa. The sorghums are remark able for their adaptability to differing conditions of soil and climate, and an almost endless list of varieties exists, which may be divided into two maingroups based upon the character of the sap. Those containing a considerable amount of sugar are classed as saccharine sorghums; those weak in sugar as non-saccharine. The name °sorghum') is applied in common use to the saccharine varieties only, while the non saccharine kinds commonly bear the name of their species, as Kaffir corn, durra, etc. The several varieties of the sweet sorghums are so nearly alike that little distinction is made in treating them as a class. The two leading varieties are the amber and the orange, the former being the favorite in the more northerly latitudes of the United States, and the latter in the South and the Southwest. Sorghum thrives in every part of the United States ex cept in the colder parts of New England and in the higher parts of the Rocky Mountains. At first it was grown exclusively for the manu facture of syrup and sugar, but as its value as a forage became known, the area de voted to its cultivation increased rapidly.
Saccharine The Civil War caused a scarcity of sugar in the United States, and sorghum syrup came into widespread use as a substitute. In 1860, five years after the first seed was introduced from China, 6,749,123 gallons of sorghum syrup were made and con sumed in the United States. In 1870 the produc
tion had swelled to 16,050,089 gallons, and in 1880 to 28,444,202 gallons. Since that time the production of sorghum has shown a steady de crease, being only 16,532,382 gallons in 1918. In the manufacture of syrup the stalks are stripped of their leaves after the seed has ripened, and the tops are cut off. The stalks are then cut off close to the ground and passed through heavy rollers to extract the juice, which is then boiled in shallow pans until a syrup of the de sired consistency is obtained. The greater part of the sorghum now manufactured is a farm product, all of the operations of manufacture being performed on the farm. In 1878 the United States Department of Agriculture took up experiments to ascertain whether sugar could be manufactured profitably from sor ghum. Two objects were aimed at in the experi ments, (1) to discover a cheap process for ex tracting the juice and making the sugar and (2) to increase the sugar content of the plant. Considerable progress was made along both these lines, and the chemists in charge of the work at one time thought that sorghum would become a competitor of sugarcane as a source of sugar. Attempts were made by capitalists to manufacture sorghum sugar on a commercial scale, but none of these attempts have proved successful. The only satisfactory process of getting the sugar to crystallize properly in volves the use of a large amount of alcohol, which, under present government regulations, is so expensive as to make the process imprac ticable.
Sorghum is valued highly by stockmen as a soiling crop, and makes good summer pastur age for all kinds of stock. Its high sugar con tent gives it an especial value in fattening swine, and it is also an excellent food for sheep. As ensilage it makes good feed, but on account of the difficulty in preventing the development of acidity in the silo, other crops are generally preferred for this purpose. Sorghum is of especial value as a pasturage plant, owing to the fact that it is at its best in midsummer, when other grasses are generally of the least service. The heavy yield of hay makes it one of the favorite forage crops. In pasturing, care is necessary on first turning stock upon sor ghum, owing to the danger of bloating.