Sapstain Development On Jack Pine Logs In Eastern Canada


  • Dian-Qing Yang
  • Robert Beauregard


Sapstain, jack pine, log storage, fungal stain, bark damage


During 1998-1999, a study was initiated to investigate the influence of seasons, log types, and storage time on the sapstain development of jack pine logs at three sites in Eastern Canada. Jack pine trees (Pinus banksiana) were harvested into full-length and cut-to-length logs in spring and in autumn. Sapstain development was examined in these logs at intervals of 2 to 4 weeks after felling. The mean stain coverage and mean maximal radial penetration of stain in wood were measured from the discs of the sampled logs. The spring trial showed that sapstain did not develop significantly on jack pine logs within 4 weeks after trees were felled; however, the severity of stain increased proportionally with storage time. The full-length logs were more stained than the cut-to-length logs in the spring felling. All logs were seriously stained after the 3 months of summer storage. The autumn trial showed that logs felled after September were stored in the sawmills over winter without significant stain, but stain development was rapid after April of the following year. Debarking logs did not reduce stain development on wood. In fact, the growth of stain was more rapid on debarked logs than on logs with the bark. The main fungus isolated from stained wood was Ceratocystis coerulescens. Bark beetle attack was found in logs within 4 weeks of the spring harvest. The species of bark beetle was Ips pint. After 3 months of summer storage, decay started to develop in these logs. The main causal species was Schizophyllum commune.


Ainsworth, G. C., F. K. Sparrow, and A. S. Sussman. 1973. The fungi—An advanced treatise. Vol. IVA: A taxonomic review with keys: Ascomycetes and Fungi imperfecti. Academic Press, New York, NY.nBehrendt, C. J., R. A. Blanchette, and R. L. Farrell. 1995. Biological control of blue-stain fungi in wood. Phytopathology 85:92-97.nClark, J. E. 1992. Fungal stain in Canadian softwood sawlogs. Canadian Forestry Service Report No. 35. Ottawa, Canada.nGibbs, J. E. 1993. The biology of Ophiostomatoid fungi causing sapstain in trees and freshly cut logs. Pages 153-160 in M. J. Wingfield, K. A. Seifert, and J. F. Webber, eds., Ceratocystis and Ophiostoma: Taxonomy, ecology, and pathogenicity. APS Press, St. Paul, MN.nHansen, E., and J. Morrell. 1997. Use of anti-stain chemical treatments by the western U.S. softwood lumber industry, 1994. Forest Prod. J. 47(6):69-73.nLee, K., and J. N. Gibbs. 1996. An investigation of the influence of harvesting practice on the development of blue-stain in Corsican pine logs. Forestry 69:137-141.nLinares-Hernandez, A., and E. M. Wengert. 1997. End coating logs to prevent stain and checking. Forest Prod. J. 47(4):65-70.nScheffer, T. C. 1969. Protecting stored logs and pulp-wood in North America. Mater. Organ. 4:167-199.nUzunovic, A., J. F. Webber, and D. J. Dickinson. 1996. Development of bluestain in commercially harvested logs in Britain. Int. Res. Group Wood Preserv. Document No. IRG/WP 96-10150.nUzunovic, A., J. F. Webber, and D. J. Dickinson. 1997. Influence of bark damage on bluestain development in pine logs. Int. Res. Group Wood Preserv. Document No. IRG/WP 97-10197.nUzunovic, A., D. Q. Yang, P. Gagné, C. Breuil, L. Bernier, A. Byrne, M. Gignac, and S. H. Kim. 1999. Fungi that cause sapstain in Canadian softwoods. Can. J. Microbiol. 45:914-922.nWengert, G., and J. Denig. 1995. Lumber drying today and tomorrow. Forest Prod. J. 45(5):22-30.nYang, D. Q., P. Gagné, A. Uzunovic, M. Gignac, and L. Bernier. 1999. Development of fungal sapstain in logs of three Canadian softwoods. Forest Prod. J. 49(2):39-42.nZabel, R. A., and J. J. Morrell. 1992. Wood microbiology—Decay and its prevention. Academic Press, New York, NY.n






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