FOR 202

FOREST MENSURATION II

Lab - Point Sample Cruise

BACKGROUND: You are employed by Trees-R-Us, a consulting forestry firm. The federal government has awarded the firm a contract to inventory the timber resource at Low Moor for future management decisions. You will be assigned a tract (shown on attached map) for performing the timber inventory.

OBJECTIVE: To determine basal area per acre, number of trees per acre & volume/acre; & perform a statistical analysis, by preparing & implementing a point sample timber cruise on a forested tract.

CREW: Individual

EQUIPMENT: d-tape, clinometer, hand compass, BAF-10 prism, 50-foot tape, Field map, tally sheets or field recorder, volume tables.

PROCEDURE:

1. Prepare a work map using a scale of 1" = 1320’

2. Using the following information, determine the number of plots needed* to achieve the desired accuracy:

        - Acceptable Limit of Error of +/- 12% (estimating basal area per acre)

        - Predicted Coefficient of Variation of 40% (variability of average basal area within tract)

        - Probability of 95% that tract is within 2 standard deviations of mean basal area

3. Based on number of plots needed* and tract acreage, determine the spacing for these plots.

4. Using BAF-10 prism, determine:

        - Basal area per acre, - Number of trees per acre

        - Sawtimber (BF) and pulpwood volume (cords) per acre

5. Determine the mean, standard deviation, coefficient of variation and limit of error of the tallied basal area per plot. Was the original estimate for CV accurate? Did you meet the target LE?

6. The final report should follow the Timber Cruise Report - General Outline and include:

        - Original field data and field map

        - Worksheets showing basal area, trees per acre and volume calculations

        - Statistical calculations

        - Final tract map showing sample locations, cruise design & major topographic features

        - Forest-cover type map, showing general cover types and size classes

        - Typed report summarizing tract information (refer to General Outline)

7. The report should be carefully & neatly prepared. The project grade will be based on:

        - Quality and accuracy of field work

        - Completeness and quality of report

        - Accuracy of cruise, BA, T/Ac, Volume and statistical calculations

        - Quality and accuracy of maps

        - Completeness and presentation of data

8. This report will be worth 10% of final course grade and will be due on  ____________.

 

TIMBER CRUISE REPORT

GENERAL OUTLINE

I. TITLE PAGE

Title, Date, Author, Crew members

II. INTRODUCTION (1-2 pages)

    A. Purpose - determine the forest condition by inventorying forest resource - to make land management decisions.

    B. General Information (background)

        1. Land description

            a. General location - State, County, Local

            b. Specific location - general boundary description, tract map

            c. Vicinity map - including scale, north orientation, date, legend

        2. Forest description

            a. Ownership - who, why, when, how

            b. Resources - general timber, wildlife, recreation, minerals, watershed

        3. Area characteristics

            a. Soils - general soil types

            b. Topography - general land of land

            c. Climate - general temperatures, precipitation, seasons

            d. History of tract

III DATA PRESENTATION - RESULTS

    A. Forest Cover (narrative and tabular)

        1. Timber types - by species groups

            a. Forest cover type map

            b. Acreages

        2. Stocking - basal area per acre, trees per acre

        3. Growth (volume per year) optional

        4. Site index - specify tree species, age, height (optional)

        5. Quality - defect (based on field observations and other sources)

    B. Volume and Value (Timber Cruise Data Summary)

        1. Sawtimber per acre - By species groups

            a. BA/acre; Trees/acre; Volume/acre; total volume; total value

            b. Graph by species groups, dbh and number per acre

            c. Sawtimber value per acre

        2.Pulpwood per acre

            a. BA/acre; Trees/acre; Volume/acre; total volume; total value

            b. Value per acre

IV APPENDIX

    A. Cruise procedure (type of cruise, # plots, plot size - if applicable)

    B. Tally sheets

    C. Calculations: "Basal area, trees/acre, volume/acre" worksheets

    D. Statistical report

    E. Field map

    F. References