The red mulberry grows to be a large dense, round-headed tree, with thick fibrous roots and milky sap. Its alternate leaves, three to five inches long, are variable in form, often irregularly lobed, very veiny, usually rough, blue-green above, pale and pubescent beneath, turning yellow in early autumn. The inconspicuous flower spikes are succeeded by fleshy aggregate fruits like a blackberry, sweet, juicy, dark purple or red, each individual fruit single-seeded. Birds and boys alike throng the trees through the long period during which these berries ripen. They are hardly worthy to rank with the cultivated mulberries as a fruit tree. But planted in poultry yards and hog pastures the dropping fruits are eagerly devoured by the occupants of these enclosures.
The chief value of the tree lies in the durability of its orange-yellow wood, which, though coarse-grained, soft and weak, is very durable in the soil and in contact with water. Hence it has always commended itself to fence- and boat-builder. It is sometimes planted for ornament, but its dropping fruit is a strong objection to it as a street or lawn tree.
One of the mulberry's chief characteristics is its tenacity to life. Its seeds readily germinate and cuttings, whether from roots or twigs, strike root quickly. Indians discovered that rope could be made out of the bast fibre of mulberry bark. They even wove a coarse cloth out of the same material. The early settlers of Virginia, who found the red mulberry growing there in great abundance, dreamed in vain of silk culture as an industry based upon this native tree. Their hopes were not realized. Silk culture has never yet become a New-World industry.
The white mulberry is a native of northern China and Japan. From this region it has been extensively introduced into all warm temperate climates. Its white berries are of negligible character. It is the leaves that give this oriental mulberry a unique position in the economic world. They are the chosen food of silkworms. No substitute has ever robbed this tree of its preëminence, maintained for many centuries in its one field of usefulness.
The hardy Russian mulberries are derived from _M. alba_. These have done much to enrich the horticulture of our Northern states, but the parent tree, though it thrives in the eastern United States and in the South, has not been the means of establishing silk culture on a paying basis in this country.