willows: their growth, use, and importance. 35 



willow set in dry soil often last five to seven years. In soils that 

 are alternately dry and wet and which freeze and thaw a great 

 deal, willow posts are shorter lived, but under such conditions the 

 life of any kind of post is much shortened. Posts of the diamond 

 willow (Salix cordata) are very durable. More willow than cotton- 

 wood posts can usually be produced on a given area in a given time, 

 especially if the trees are planted in rows, and willow posts are gen- 

 erally set in preference to cottonwood. 



Willow wood is light, fairly porous, and quite easily treated. 

 A treated willow post is practically as good as a treated post of any 

 other species and much more durable than an untreated post of most 

 species. Where good cedar, catalpa, locust, or Osage orange posts are 

 obtainable for 20 to 30 cents, it would scarcely pay to use treated 

 posts, but in many parts of the Middle West the average price of a 

 red cedar post is approximately 40 cents. At this price it would be 

 economical to use treated willow posts. First-class willow posts can 

 be grown on good farm land for 12 cents apiece and second-class posts 

 for 8 cents. These can be treated at a cost of 10 cents. Including 

 the cost of peeling at 3 cents each, the cost of first-class creosoted 

 posts is 25 cents and second-class posts 21 cents. Willow posts 

 should be seasoned 8 or 10 weeks before being treated. Round posts 

 are better for this purpose, as the penetration is better in sapwood 

 than in heartwood. A willow post properly treated should last from 

 12 to 20 years. There seems to be a decided difference in opinion as 

 to the value of seasoning untreated willow posts. At one experiment 

 station it was found that usually seasoning was of little importance, 

 but experience elsewhere does not altogether corroborate this observa- 

 tion. At Iowa Falls, Iowa, willow posts cut in the winter, seasoned 

 with the bark on, then peeled and set out the following autumn, have 

 had an average life of 10 years. At the same place willow posts cut 

 in June and set out immediately lasted only 2 or 3 years. At 

 numerous places in the prairie region seasoned willow posts have 

 lasted 10 years, while most reports of decay in a short time also show 

 that the posts were not seasoned. In setting willow posts care should 

 be taken to avoid using material with doty heartwood. It may 

 easily escape notice because the heart of willow shows very little dis- 

 coloration until decay is far advanced. 



TANNIN. 



Willow bark is an important source of tannin in Europe, especially 

 in Russia, France, Denmark, and Germany. In Russia it is used in 

 the preparation of the finest leather, and combined with birch tar oil 

 it produces the well-known scent of Russia leather. Von llohnel 

 sf sites flint the cruck willow (Stil.i.r, fmf/'dis) and basket willow (Salix 

 viminalis) arc the best for this purpose, containing 12 to 14 per cent 



