178 ELEMENTARY FORESTRY. 
TABLE SHOWING RANGE OF DURABILITY OF FENCE POSTS IN 
MINNESOTA. (Air dry.) 
IROUNG eclipses eos yn away ph let cma ethan ee stocks jake eae ats 30 years 
White Cedar (quartered 6-inch face)................1TO-15 years 
Waite (Oak: (Gneh 1outid) weiss agnaceseead anu sass dc 8 years 
Redsand Black *@ alesse socom cenieetccne ene ene 4 years 
Tamarack CRedwood)) ssa ee:acx.aedtensyeenaaneteas 9 years 
PUTT etn ken eevee eat a ere eee ol esata Sgt atece Gorin teas a. SORT VeArS 
Ash Beech, Maplevic.isuete soda. nkeiy oankainn ie saan 4 years 
Black Walnut ......... .. 7-10 years 
White Willow, 6 inches in diameter, peeled and dried. 6-7 years 
Curing is one of the most important processes in its effect 
on the durability of wood. Well cured wood resists decay far 
better than fresh wood, because it contains an insufficient amount 
of water for the growth of fungi. Green wood covered with 
paint before it is dry is often destroyed by dry rot, since this 
fungus finds abundant moisture under the paint and the protec- 
tion which was intended for the wood really protects its enemy, 
the fungus. Paint and other wood-protecting compounds are 
efficient only when they are applied to dry material, which they 
preserve by protecting them from moisture. But fence posts or 
other timber to be used in moist places, if well cured, will, even 
if not protected, last much longer than fresh cut timber. The 
amount of moisture in wood, then, is the most important factor 
in influencing its durability. 
Timber is Best Cured Under Cover, where it is pro- 
tected from the sun and the full force of the wind, but has a 
good circulation of air. If piled in the open, it is a good plan to 
shade it. When piling green or wet timber, place lath or other 
strips of wood of uniform size under each log, post or tie. In 
piling sawed lumber the lath should be placed at the ends, as in 
this position they in a measure prevent checking on the ends. 
From twelve to eighteen months is generally sufficient to cure 
wood for ordinary use, while for special work ten or more years 
may occasionally be required. If green or wet timber is closely 
piled in warm weather it is likely to rot. The best method of 
curing timber without resorting to the use of expensive appa- 
ratus is to work it up at once and soak it in water for from one 
to three weeks to remove the sap from the outside of the wood. 
