Control of Interior Darkening in Hard Maple

Authors

  • Hwanmyeong Yeo
  • William B. Smith

Keywords:

Wood color, interior darkening, internal temperature, moisture content, L*a*b* color values, enzyme-mediated processes

Abstract

Industrial experience and research have shown that hard maple lumber color changes are very often affected by the temperature and relative humidity conditions the wood is exposed to during drying. For this reason, appropriate kiln schedules should be selected and properly used to control not only surface, but entire board color. In this research study, a technique was developed that successfully demonstrated occurrence of interior darkening of hard maple at particular drying temperature and moisture content conditions. Results show that the critical temperature causing this interior darkening is 110°F, and it particularly develops with elevated temperatures while the MC is at and above the FSP. There appears to be minimal color change when drying below the FSP.

References

Bailey, I. W. 1911. Oxidizing enzymes and their relation to "sap stain" in lumber. Botanical Gazette50(26):142-147.nCIE. 1986. Colorimetry. CIE Publication No. 15.2. 2nd ed. Commission Internationale de l'Eclairage, Vienna, Austria. 74 pp.nForsyth, P. G., and T. L. Amburgey. 1991. Microscopic characterization of nonmicrobial gray sapstain in southern hardwood lumber. Wood Fiber Sci.23(3):376-383.nForsyth, P. G., and T. L. Amburgey. 1992. Prevention of non-microbial sapstain in hardwoods. Forest Prod. J.42(3):35-40.nHardwood Review Weekly. 2002. Vol. 19, Issue 13. Charlotte, NC.nMcMillen, J. M. 1975. Physical characteristics of seasoning discolorations in sugar maple sapwood. USDA For. Ser. Res. Paper FPL248. Forest Prod. Lab., Madison, WI.nMcMillen, J. M. 1976. Control of reddish-brown coloration in drying maple sapwood. USDA For. Ser. Res. Note FPL-0231. Forest Prod. Lab., Madison, WInPrice, E. W. 1982. Chemical stains in hackberry can be prevented. Southern Lumberman. March. Pp. 13-15.nSchmidt, E. L., and T. L. Amburgey. 1994. Prevention of enzyme stain of hardwoods by log fumigation. Forest Prod. J.44(5):32-34.nSimpson, W. T. 1988. Dry kiln operator's manual. USDA Agriculture. Handbook. No. 188. Forest Prod. Lab. Madison, WI.nSmith, W. B., and D. J. Herdman. 1998. Effects of kiln schedules and sticker variables on board color and sticker stain in hard maple. Pages 121-133 in Proc. 26th Annual Hardwood Symposium: Technology and Market Information for the Next Millenium. National Hardwood Lumber Association, Memphis, TN.nSmith, W. B., and D. E. Montoney. 2000. Wood color change and control during drying. Pages 111-118 in Proc. Quality Lumber Drying in the Pacific Northwest—Vertical Integration—Improved Profit, September 30—October 2, 1999, Seattle, WA. Forest Prod. Society, Madison, WI.nSmith, W. B., H. Yeo, P. Rappold, D. Herdman, and D. Montoney. 2003. Wood color and stain control. Pages 91-102 in Proc. Quality Drying: The Key to Profitable Manufacturing, September 23-25, 2002, Montreal, Quebec. Forest Prod. Society, Madison, WI.nWengert, E. M. 1992. Causes and cures for stains in dried lumber: Sticker stain, chemical stain, iron stain, and blue stain. Univ. of Wisconsin Forestry Facts No. 64. Madison, WI.n

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Published

2007-06-05

Issue

Number 3 / July 2004

Section

Research Contributions

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