USE OF PEEISHABLE WOODS FOR FENCE POSTS 199 



Every woodlot contains trees large enough and strong 

 enough that could be used for fence posts if it were not for 

 the fact that the wood rots easily and quickly when put in 

 the ground. Soft and hard maple, box-elder, ash, elm, beech, 

 poplar, sycamore and other trees would be as serviceable as the 

 best of cedar or locust if the wood were durable. Many of 

 these trees, too, are fast growers. Cottonwood will grow to 

 fence post size in 15 years or less, ash in 20 years, maple in 

 20 years, red oak in 25 years. 



How can the trees that commonly grow in woodlots, but 

 which do not produce durable woods, be utilized for fence 

 posts ? Can wood be made durable ? 



Wood decays because of the destruction of the cells by 

 low forms of plant life called fungi, as has already been 

 explained. When the spore of the fungus plant falls on 

 moist wood it will start to grow. It sends out filaments into 

 the wood consuming the fibers and causing decay. Like other 

 forms of plant life, fungi require for their development heat, 

 air, food and moisture. The reason a fence post decays most 

 quickly at the surface of the ground is because there the 

 conditions are most favorable for the growth of the fungi. 

 Below the surface a post rots very slowly because of insuf- 

 ficient air, and above the surface the post rots slowly because 

 the post dries out quickly after a rain. Any wood in con- 

 tact with the ground or placed where it will be kept constantly 

 moist will in time decay. If the fungus is deprived of any 

 one of the factors of growth mentioned it cannot live and th<j 

 wood will not decay. If wood is kept dry it will not decay. 

 A table made even of a very perishable wood like birch or 

 hickory will last indefinitely if kept in the house. Wood con- 

 stantly covered with water cannot decay because of the lack 

 of air for the development of the fungus plant. Bog oak logs 

 are dug from the swamps in Ireland, where they have lain 

 for centuries, and made into furniture. Wood decays very 

 slowly in cold regions, because fungi need warmth. Wood that 



