Eric, As someone who has worked in both Saskatchewan and Virginia, i think you should get an 18" corer ... if you encounter floodplain white spruce or balsam poplar, (even trembling aspen on some rich uplands) you may come across 40-80cm dbh stems (same for many pre-1930's Appalachian hardwoods). Also, i recommend getting the 5mm+ variety, as the thin ones are more likely to fall apart, and are more difficult to analyze if you are going to measure the full sequence of rings. If embarking on a full summer of field work, i strongly recommend you take at least 2 or 3 borers with you, as they will inevitably get stuck, dull, or damaged (one 18" and two 12" should see you through a few thousand stems). Suggested Reading (i.e., full of many practical hints): Jozsa, L. 1988. Increment core sampling techniques for high quality cores. Special Publication No. SP-30, Forintek Canada Corp. 26 p. available from their Vancouver Lab (tel 604-224-3221) or their Ottawa lab (tel. 613-744-0963) Phipps, R.L. 1985. Collecting, preparing, cross-dating, and measuring tree increment cores. Water Resources Investigations Report 85-4148, U.S. Geological Survey, Reston, Virginia. 48 p. Maeglin, R.R. 1979. Increments cores: how to collect, handle, and use them. GTR FPL 25, U.S.D.A. Forest Service, Madison, Wisconsin. 18 p. Good luck, Phil Burton ========================================================================= burton@unixg.ubc.ca /* "Several Nations, One Canada, TNSF" */ Philip J. Burton, Assistant Professor University of British Columbia Department of Forest Sciences tel. 604-822-6020 #270 - 2357 Main Mall fax. 604-822-5744 Vancouver, B.C. Canada V6T 1Z4 =========================================================================
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