2409.12-2015-2
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FOREST SERVICE HANDBOOK
TONGASS NATIONAL FOREST
KETCHIKAN, ALASKA
FSH 2409.12 – TIMBER CRUISING HANDBOOK
CHAPTER 10 – PRINCIPLES OF MEASURING TREES
Supplement No.: R-10 TNF 2049.12-2015-2
Effective Date: 04/06/2015
Duration: This supplement is effective until superseded or removed.
Approved: /s/ Forrest Cole
Forest Supervisor
Date Approved: 04/06/2015
Posting Instructions: Supplements are numbered consecutively by Handbook number and
calendar year. Post by document; remove the entire document and replace it with this
supplement. Retain this transmittal as the first page(s) of this document. The last Tongass
supplement to this Handbook was 2409.12-2015-1 to chapter 20.
New Document
2409.12 – 2015-2
3 Pages
Superseded Document(s) by
Issuance Number and
Effective Date
N/A
xx Pages
Digest: New direction for the Tongass National Forest
14.2 - Measuring Tree Heights
Use total tree height when measuring tree heights. Measurement will be taken from one-foot
stump height on the high ground side to the tip of the tree leader, for trees with broken tops
cruise to merchantable height. Measure from one-foot stump height on the high ground side to
the break and take a top diameter inside bark at this point with a Relaskop (see example 1). If the
top diameter at the break is less than 6”, measure the merchantable height at a point where 6” is
attained and record total tree heights to the nearest foot. Record in the notes “cruised to
merchantable height.”
R-10 TNF SUPPLEMENT
EFFECTIVE DATE: 04-06-2015
DURATION: This supplement is effective until superseded or removed.
2409.12-2015-2
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FSH 2409.12 – TIMBER CRUISING HANDBOOK
CHAPTER 10 – PRINCIPLES OF MEASURING TREES
Example 1:
Calculate the number of logs and cruise/defect accordingly. Do not use table #4 from the Coastal
Alaska Field Guide for Old Growth Cruising to calculate the number of logs (see example 2).
Example 2: Merchantable height is 58’ with 12” Top DIB = first log 32’ + second log
26’ = 1.5 logs. The second log will have to be manually entered into FSCruiser. Even though the
Log Data screen shows zero for tree height and .5 logs it will calculate the volume to 58’. Deduct
only for seen defect, do not defect beyond 58’.
R-10 TNF SUPPLEMENT
EFFECTIVE DATE: 04-06-2015
DURATION: This supplement is effective until superseded or removed.
2409.12-2015-2
Page 3 of 3
FSH 2409.12 – TIMBER CRUISING HANDBOOK
CHAPTER 10 – PRINCIPLES OF MEASURING TREES
A live tree with a broken top with a merchantable log in the top portion that is lying on the
ground, measure the actual height and cruise/defect accordingly (see example 3).
Example 3:
1. Measure height of the stub (A).
2. Measure length of the piece on the ground (B).
3. Add the two measurements to obtain the total height, A+B=Total ht.
It has been determined by our appraisal staff that a grade#6 (special mill) and a grade #2 in
spruce and hemlock have similar value, therefore we will no longer cruise for grade #6; they
will all be grade #2. Grading of Alaska Yellow Cedar will remain unchanged.
Western Red Cedar will be graded #5 on all merchantable logs, use grade #8 on logs not meeting
the merchantability specifications.