Please see enclosed request from Sylvametrics Consulting and respond
directly to them as appropriate.
Thanks, Gyde.
H. Gyde Lund, USDA Forest Service - FIERR, P.O. Box 96090,
Washington, DC 20090-6090 USA. Tel: +202-205-1147; Fax:
+202-205-1087; Email: fswa/s=g.lund/ou=w01c@mhs.attmail.com
Content-Type: text
Content-Length: 00000001747
ESTIMATION OF DEFECT VOLUMES IN OPERATIONAL INVENTORY
Sylvametrics Consulting is undertaking a rapid survey of defect estimate
methods used in operational inventories (timber cruising) on behalf of the
British Columbia Ministry of Forests.
Two methods are currently used in BC:
1. Loss factor tables. A large data base of destructive samples is used to
calibrate tables which predict percent loss in whole stem volume, according
to classes of external indicators of decay and damage, species, age, and
geographic location. This is the method currently employed for all
government approved operational inventories.
2. Cruiser-called netfactors. Cruisers (the field inventory technician)
visually estimate the net sound volume of the tree by log position, based
on external indicators and local knowledge of defect amounts as observed in
log scaling (tally). this method is used by some of the larger companies on
operational inventories that do not require government approval.
The Ministry of Forests is considering changing the methods they use to a
method that will combine aspects of the above two approaches.
Sylvametrics is documenting methods that are approved or are widely used in
other jurisdictions and would appreciate any information you can share with
them in this regard. A brief description of the method you use, any sampling
and research that underlies the method, and an assessment of the degree of
satisfaction there is in the method would be appreciated. Please send your
responses to Sylvametrics Consulting, #109-1034 Johnson Street, Victoria, B.C.
V8V 3N7 Canada. Tel: +604-361-3290. Fax: +604-361-9307. Email:
sylva@sol.uvic.ca
Mail converted by
MHonArc 1.1.0