246 TREES OF MINNESOTA. 
SALICACEAE. WILLOW FAMILY. 
A large family of trees and shrubs, mostly inhabiting cold 
climates. Leaves alternate, simple, undivided, and furnished 
with stipules which are scale-like and deciduous, or leaf-like and 
persistent. Flowers, dioecious, both kinds in catkins, one under 
each bract or scale of the catkin, without calyx or corolla; in 
some cases the calyx is represented by a gland-like cup; ovary 
one or two-celled. Fruit a one or two-celled, two-valved pod, 
with numerous seeds attached to a parietal or basal placenta, 
ripening in early summer and furnished with long, silky down. 
Genus SALIX. 
Leaves generally narrow, long and pointed. Flowers appear 
before or with the leaves, in terminal or lateral, cylindrical, 
imbricated, generally erect catkins; two or more distinct or 
united stamens; stigmas two, short. Fruit a one-celled two- 
valved pod. Trees or shrubs with smooth round branches, usu- 
ally found growing in moist land. A large and valuable genus 
of over 160 species, the greater number belonging to Europe and 
Asia. About sixty species belong to North America. A dwarf 
willow is found growing the farthest north of any shrub. Only 
two tree-like species are indigenous within our range, but there 
are several foreign kinds mentioned here that are of much value 
for cultivation in this climate. 
Propagation.—The willows increase readily from cuttings, and 
are seldom grown in any other way. The cuttings grow readily 
at almost any season of the year, provided they are put in moist 
soil. Even in midsummer cuttings of firm wood a half inch or 
more in diameter will grow readily if planted in moist soil, but 
the best time to make cuttings is in the fall or spring, when wood 
of any age or size will root if properly planted. Some of the 
weeping varieties are grown by top-working in upright stocks. 
Uses.—The bark of the trees of all species of Salix with bitter 
bark yields salicylic acid, which is now used medicinally in the 
treatment of typhoid fever, gout and rheumatism. During the 
Civil War ground willow bark was used in the treatment of 
fevers in some of the Southern hospitals when quinine could not 
