M. álba.
2. Mòrus álba, L. (White Mulberry.) Leaves obliquely heart-ovate, pointed, serrate, smooth and shining; lobed on the younger growths; 2 to 7 in. long. Fruit whitish, oval to oblong; ripe in July. A small tree from China, planted for feeding silkworms, but now naturalized throughout.
Var. multicaulis has large leaves, and is considered better for silkworm food than the usual form. It is not very hardy, as it is frequently winter-killed in the latitude of New York City.
Var. Downingii (Downing's everbearing Mulberry) has large leaves and very large, dark red or black fruit, of excellent flavor, which does not ripen all at once as most Mulberries do.
Genus 79. BROUSSONÈTIA.
Trees with milky juice and alternate, deciduous, stipulate, broad, very hairy leaves. Flowers diœcious. Fruit (only on a portion of the plants) similar to the common Mulberry.
B. papyrífera.
Broussonètia papyrífera, L. (Paper-mulberry.) Leaves ovate to heart-shaped, variously lobed, deeply so on the young suckers, serrate, very rough above and quite soft-downy beneath; leaves on the old trees almost without lobes; bark tough and fibrous. Flowers in catkins, greenish; in spring. Fruit club-shaped, dark scarlet, sweet and insipid; ripe in August. Small cultivated tree, 10 to 35 ft. high, hardy north to New York; remarkable for the great variety in the forms of its leaves on the young trees.