82 ILLINOIS NATURAL HISTORY SURVEY CIRCULAR 51 



Mulberry 



The red or American mulberry {Morus rubra) is native to 

 America. However, the white mulberry (M. alba) was intro- 

 duced from eastern Asia in colonial times when there was an 

 attempt to establish the silkworm industry in the United States. 

 Red, white, and Russian mulberry {M. alba tatarica) , a variety 

 of the white mulberry, are used occasionally in ornamental plant- 

 ings. However, their large, juicy fruits, which are attractive to 

 birds, insects, and other animals, become very messy when they 

 fall to the ground. 



Red mulberry is a dense, broad, round-topped, fast-growing 

 tree with stout, spreading branches that are resistant to injury 

 by ice and wind. It reaches a height of 40-60 feet. It grows best 

 on rich, moist soils. The thin, bluish-green, oval to nearly circu- 

 lar or somewhat heart-shaped, alternate leaves are entire to 

 three-lobed and 3-5 inches long and 21/2-4 inches wide. Some 

 leaves with single lobes are mitten shaped. They are smooth to 

 somewhat roughened above, pale and more or less hairy beneath, 

 and have coarse, incurved teeth along the margins. The leaf 

 stems contain a milky sap. Male and female flowers, which ap- 

 pear as the leaves unfold, may be borne on separate trees or on 

 the same tree — the male flowers as 2-inch-long, narrow catkins, 

 and the female flowers as 1-inch-long, hanging spikes on short, 

 hairy stalks. The long, narrow, dark red to purple, sweet, juicy, 

 edible fruit is over an inch long and hangs by a short stalk. The 

 red-tinted, brown, rather thin bark peels off in long, narrow 

 plates or flakes. Red mulberry is relatively free of diseases but 

 many insects, especially caterpillars, feed on the leaves. The soft, 

 coarse-grained, golden-brown wood is sufficiently tough and dur- 

 able to be used as fence posts. 



White mulberry (Fig. 77) is a small, round-headed tree, 

 with wide-spreading branches, which grows to a height of 50 

 feet. The small, thin, broadly egg-shaped, alternate leaves (Fig. 

 77 insets), 21/4-7 inches long, are light green and smooth above 

 and slightly hairy beneath. The pointed-topped and rounded or 

 heart-shaped leaves often have one to five lobes and are smooth 

 except for hair on the veins. The margins are coarsely toothed. 

 The small, greenish flowers are similar to those of red mulberry. 

 The sweet but insipid fruit is V-j-l inch long and white to pink 

 or purplish violet. The bark has more of a yellowish tinge, espe- 

 cially in the furrows, than the bark of red mulberry. 



Russian mulberry is a hardy, small, bushy tree which grows 



