WILLOWS: THEIR GROWTH, USE, AND IMPORTANCE. 5 
There are several forms of the white willow, one of which, the yellow 
willow (Salix alba vitellina), is as common as the white willow. The 
bright yellow bark of this variety and its greater inclination to 
branchiness readily distinguish it. 
The white willow has pale-green leaves with silky pubescence on 
both sides, but at maturity the upper surface is nearly smooth. 
The edges are finely toothed. The mature leaves are from 2 to 4J 
inches long and from one-third to two-fifths of an inch wide. The 
bark is from half an inch to 1J inches thick on large trees, dark 
brown on the trunk with a reddish tinge higher up. It is deeply 
divided into broad, flat connecting ridges. Green, yellow, and red 
twigged forms are known to the trade. 
CRACK WILLOW. 
(Salix fragilis L.) 
The crack willow, or gray willow, as it is often called, is quite 
similar in general appearance to the white willow. Under the same 
conditions it easily reaches the size attained by the white willow, 
but is in general a more slender and better formed tree. It is easily 
distinguished from the white willow by its larger, coarsely notched 
leaves and by its reddish-green twigs, which are extremely brittle 
at the base. The leaves are from half an inch to 1 inch wide, nar- 
rowed at the base, and from 3 to 6 inches long. At maturity they 
are smooth on both sides, dark green above and paler beneath. 
The bark is smooth and green on the upper portions of the tree. 
On the lower trunk it is rough, scaly, ridged, gray-brown, and 1 
inch to 1J inches thick. The crack willow does not produce so 
many water sprouts along the trunk as the white willow and there- 
fore makes cleaner timber. It is undoubtedly the best willow 
species for plantations in the Prairie States. Many of the so-called 
white willow plantations are really crack willow. It is commonly 
planted in eastern, central, and northern United States. A yellow 
form is occasionally found in the nursery trade. 
WEEPING WILLOW. 
(Salix babylonica L.) 
The weeping willow is another of the introduced species that is 
now widely scattered over the United States. Though a rapid 
grower at first, it does not reach the size attained by the white and 
crack willows. The height is seldom over 50 feet, but may occasion- 
ally reach 60 feet. The diameter is often from 3 to 5 feet when the 
tree is grown in the open. The weeping willow can readily be dis- 
tinguished from the white willow, which it most closely resembles, by 
