Variations in Moisture Content of Air Seasoned Southern Pine Lumber in Georgia

Variation in moisture content in stacked, air-seasoned lumber was studied. Four methods of stacking in common use in Ga were studied: flat-, package-, end- and crib-piled lumber. Information obtained came from 21 stacks containing approximately 42 Mbf of lumber. Individual boards (8,846 bd.ft.) were studied for seasoning degrade and moisture content. Moisture content studies were made to find the effect of stacking methods on drying times and on the uniformity of lumber moisture content. Resistance type meter was used for taking moisture measurements. The piles studied had been stacked for periods ranging from 19 to 173 days. There was considerable lack of uniformity in moisture content of the piles studied. Though pile averages were less than 20 percent, about 15 percent of the individual boards studied had moisture contents above 19 percent, the limit accepted by the Southern Pine Inspection Bureau for air-dried lumber. In all methods of piling, there was a moisture gradient from low at top to higher moisture content at the bottom. Contrary to expectations variability in moisture content was found to be greatest at the top of the piles. The ranges were from 20 to 35 percent at the top and from 9 to 24 percent at the bottom. The four common methods of piling southern pine lumber for air-seasoning resulted in average moisture contents below 20 percent after 3 weeks of good weather. Lack of uniformity was most serious in crib-piled lumber. End-piled lumber dried rapidly. Contrary to expectation, flat-piled lumber showed the greatest uniformity, while package units were the poorest. Flat-piled lumber, however, had the highest degrade losses.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member