36 



BULLETIN 316, U. S. DEPARTMENT OF AGRICULTURE. 



of tannin, while other species contain 6 to 11 per cent of tannin. 

 H. G. Bennett in "The Manufacture of Leather" asserts that crack 

 willow and S. arenaria contain 7 to 11 per cent of tannin and are 

 commonly used. Alexander Watt in "Leather Manufacture" states 

 that the bark of white willow (S. alba) and S. cinerea is used for 

 tannin in France. 



Tests made by the leather and paper laboratory of the Bureau of 

 Chemistry of willow bark collected in 1914 at Arlington, Va., by the 

 Forest Service, produced amounts of tannin as follows: 



Table 16.- — Tannin in willow bark. 



Species. 



Per cent 



total 

 dissolved 



solids. 



Per cent 

 soluble 

 solids. 



Per cent 

 nontannins. 



Per cent 

 tannins. 



Number of 

 samples. 



S. nigra (trunk) 



S. alba (trunk) 



S. fragilis (trunk) 



S. fragilis (branches) 



16.16 

 18.13 

 23.32 

 19.62 



15.10 

 17.03 

 22.27 

 18.04 



9.40 

 14.12 

 9.64 



6.71 

 7.63 

 8.49 

 8.40 



Hemlock, chestnut oak, Spanish oak, black oak, hickory, and 

 chestnut wood range above willow in tannin content, but in some 

 cases the high tannin content is offset by the difficulty of securing 

 or handling the bark. 



The bark left in the woods in the making of excelsior and the peel- 

 ings from basket willows, of which a large amount is often collected 

 in one place, could be utilized at a low cost. If manufacturers of 

 tannin extract could be interested in willow bark and assured of a 

 sufficient supply, a profitable industry might be established. 



OTHER USES. 



Willows, because they produce flowers from which a high grade of 

 honey can be obtained, have long been recognized as a useful bee 

 plant, especially in early spring. Many beekeepers have set out 

 willows especially for this purpose. Great care should be exercised 

 in such planting to make sure that the cuttings are from staminate 

 trees, as the pistillate flowers are of little value as a bee food. 



In New Jersey, Delaware, and eastern Maryland willow is used for 

 berry props and poles in truck gardening. For this purpose it is 

 only fairly durable, but it is cheap and easy to secure. 



The freedom of willow wood from checking and the ease with 

 which it is worked make willow desirable as a carving wood and for 

 picture frames, wooden shoes, and woodenware, such as bowls, scoops, 

 ladles, and trays . 



