Weeping willows are favorites in parks and pleasure grounds, and it used to be the fashion to plant them in cemeteries, at the heads of gravestones.
Everybody who has tried to preserve bird skins, or the skins of small animals, doubtless knows what salicylic acid is, but not everybody knows that this is obtained from the bark of willows and poplars. Some species of willow contain a great deal of the substance from which salicylic acid is made.
Salicylic acid prevents animal tissue from decaying, and it is also used as a medicine. It is not poisonous, but is rather unpleasant to handle, as it is apt to make one sneeze.
The bark of willows is also used in Europe for tanning, instead of oak or hemlock bark, which is commonly used in this country.
“Tan bark” is bark that has been ground up and had the “tannin,” or substance that hardens leather, extracted from it. The tan bark is then put on roads or walks, or sometimes on city streets, to deaden the noise. It is often used in the country for banking up houses in the winter.
Willows grow quickly, and some of those that like wet places are often planted on sandy shores of lakes or streams, or on banks, that their roots may bind the sand or loose earth together and so keep the shore from shifting.
Very often a willow twig can be made to grow by merely sticking the cut end in damp earth, and many a large willow has thus been planted as a twig by the hand of a little child.