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					FOR 220       Air Photo Interpretation and Forest Measurements

Extra Credit Opportunity (8pts.)


You have been hired by a consortium of federal and state agencies to help develop
a comprehensive assessment of unmanaged stands in the Greater Yellowstone
Ecosystem. Forest ecologists in your client agencies need to establish baseline
stand structure information in stands that have had little or no management and
“natural” fire regimes. The following data were gathered during a pilot cruise of a
lodgepole pine stand in southern Montana using the big-BAF point sampling
protocol. There were 10 points installed in the 10-acre stand, which is un-even aged
and has experienced an unknown number of fires over the last 150 years. Your job
is to derive an estimate of the stand basal area and volume (in square feet per acre
and board feet per acre) and their respective 95% confidence intervals from these
data.

Use the following criteria and information during your effort: (1) use the interior
lodgepole pine volume equation given below and/or on the course website as an
Excel spreadsheet, (2) use 5-inch diameter classes and 10-ft. height classes, (3)
assume an infinite population, (4) estimate board foot volume of the entire tree,
including top and stump (BVTS in our volume equation spreadsheet), and (5) use t =
2.0 for statistical calculations.
Gallatin National Forest. 6 June 2002. 10:45. Stand 1239




              Point       BAF         Tally        dbh     Height
              1           10          7
                          40          1            13      95
                          40          1            30      145

              2           10          6
                          40          1            14      95
                          40          1            17      115
                          40          1            22      117

              3           10          10
                          40          1            11      80

              4           10          4

              5           10          5
                          40          1            15      100
                          40          1            20      115

              6           10          6
                          40          1            10      75

              7           10          13
                          40          1            12      85

              8           10          8
                          40          1            13      90
                          40          1            8       55
                          40          1            16      95

              9           10          11
                          40          1            7       45
                          40          1            20      118

              10          10          3
                          40          1            21      116
                          40          1            15      90
                          40          1            27      128
Lodgepole pine (Pinus contorta) volume equation

CVTSL   2.615591  1.847504  log DBH   1.085772  log HT 

            CVS TL
CVTS  10                           (Inverse-log10 of CVTSL)

BVTS  CVSTL 12

Where:
DBH      = DBH (cm) (Convert to inches as DBH/2.54)
HT       = HT (m) (Convert to feet as HT/0.305)
CVTSL    = LOG BASE 10, CUBIC FOOT VOLUME, INCLUDING TOP AND STUMP
CVTS     = CUBIC FOOT VOLUME, INCLUDING TOP AND STUMP
BVTS     = BOARD FOOT VOLUME, INCLUDING TOP AND STUMP, NO KERF


Hint: Download the Lodgepole Pine volume equation from the
course website!




See page 249 of Avery and Burkhart (2003) for hints on calculating standard error and 95%
confidence intervals for point sample data.

Read the section and the sample calculations carefully.

You might need to add another column or two to your volume calculation table.

Remember: Do NOT use the finite population correction factor in your standard error
calculation.

What to turn in:

1. Your stand basal area estimate, and its 95% confidence interval.

2. Your stand volume estimate and its 95% confidence interval.

3. A printout or copy of the table used to calculate your estimates of basal area, volume,
and their respective standard errors. This will likely be an Excel spreadsheet.

Organization and legibility are important.