willows: their growth, use, and importance. 27 
The wood of the male trees of the white willow is heavier than that 
of the female trees of the same species 1 and on the same soil. This 
may be due to the usually faster growth of the pistillate trees that 
has been frequently observed. In planting to obtain wood for a 
particular purpose this characteristic should be taken into considera- 
tion. 
Willow wood in the sap is whitish to creamy yellow and in the 
heart pink to reddish brown. Occasionally the heart of the black 
willow of the lower Mississippi is a light bluish gray when dry. 
The annual rings of all willows are relatively indistinct, the wood 
being quite uniform throughout. The rings of white and crack 
willow are much less distinct than those of the black willow. The 
black willow can be readily distinguished from the other two species 
even without a hand lens, provided a smooth transverse surface is 
cut. No clear and constant distinction was found between the white 
and crack willows. The white willow shows a tendency toward 
being more porous in the early wood, the pores often being larger 
than those in the crack willow, so that the medullary rays bend 
around them, but their character is not constant and occasionally 
the crack willow shows the same structure. 
TO DISTINGUISH WHITE AND BLACK WILLOW WOOD. 
In the black willow wood {Salix nigra) the pores diminish consid- 
erably in size and number toward the outer portion of the growth 
ring, with a strong tendency toward being grouped in wavy tangen- 
tial lines in the late wood. The heartwood is of a dirty reddish- 
brown or grayish-brown color. In the white willow wood (Salix 
alba vitellina and Salix fragilis) the pores diminish only slightly in 
size and number toward the outer portion of the growth ring and do 
not have the tendency toward being grouped in wavy tangential 
lines in the late wood. The heartwood is of a clear salmon-brown 
color. 
USES OF WILLOW WOOD. 
LUMBER. 
According to census reports and millmen in the South, willow 
lumber has been cut in limited quantities for the last 8 or 10 years. 
It was marketed and used locally under the name of black or brown 
cottonwood until the last 7 years. Since then the production has 
increased until willow has found a place on the market under its 
true name. Practically all of the material so utilized has been cut 
from the black willow on the lower Mississippi, principally between 
Memphis, Tenn., and Baton Rouge, La., although small quantities 
1 E. It. Piatt, " The variations of Salix alba," Quar. Jour. Forestry. 
