The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
D. Mitchell Flinchum
APR 11 1986
I.F.A.S.- Univ. of FB.r.
Florida Cooperative Extension Service / Institute of Food and Agricultural
Sciences / University of Florida / J. T. Woeste, Dean for Extension
D. Mitchell Flinchum is an Associate Professor- Extension Forest Management
Specialist, School of Forest Resources and Conservation, Institute of Food
and Agricultural Sciences, University of Florida, Gainesville, Fl 32611.
IDENTIFYING AND MEASURING FOREST PRODUCTS
Before making a timber sale, you should know what you have
to sell: how much you have and about what it is worth. A
professional forester can advise you on which products you have
and can also give you estimates regarding the amount. In most
cases the forester's experience with timber sales and his
knowledge of the current markets can increase your revenues far
in excess of his fees. If professional services are not avail-
able, however, you can follow a few basic techniques to roughly
identify and estimate the forest products on your land.
Basic size criteria of trees are diameter at 4.5 feet above
the ground (DBH) and height. The height, in feet, may be
measured as total height in some instances. In others the
merchantable height, or the distance to some specified top stem
diameter, is needed. Both measurements can be taken with a
scale stick, available from most forestry supplier companies,
but there are other ways.
made from a
calipers for measuring the diameters of trees can be
framing square and small wooden strips (Figure 1).
be estimated by leaning an 8- or 16-foot pole or
to the tree and judging how many 8- or 16-foot
in the tree.
Figure 1. Modifying a carpenter's square to make calipers for measuring the
diameter of trees.
GENERAL PRODUCT STANDARDS
Certain hardwood species in Florida may be sold for pulpwood,
sawtimber, and veneer. Markets for pine include pulpwood, chip-n-
saw, sawtimber, plylogs (or peelers) and poles (Table 1). The
diameter limit for both hardwood and pine pulpwood is 4 inches at
the smallest end.
Pine chip-n-saw products are trees that will produce some
dimension stock (generally 2 by 4s) by means of a special type
saw. In the process the wood that is chipped away to make the
dimension stock is used for pulp. Chip-n-saw trees must be 8-inch
DBH with at least 16 feet of trunk before reaching a top diameter
of 6 inches.
To qualify for sawtimber (either hardwood or pine) a tree
must have a diameter greater than 10 inches and at least one
16-foot log, 8 inches or larger at the small end.
Table 1. General standards for southern forest products
Minimum Tree Characteristics
DBH Merchantable Form
Pulpwood Low 4" 16' to a 4" Relatively
Chip-n-saw Intermediate 8" 16' to a 6" Straight,
diameter few large
Sawtimber Intermediate 10" 16' to an 8" Straight,
diameter few large
Plylogs Intermediate 12" 17' to an 8" Relatively
Poles High 10" 35' to a 7" Very
Although not common in Florida, there is a veneer market for
yellow poplar and other mixed hardwoods. Diameters must always
measure at least 12 inches DBH and the minimum log length is 16
feet. Pine peelers or plylogs are processed similar to hardwood
veneer logs. Unlike hardwood veneer which is used in the
furniture industry, the pine is used for the manufacture of
Pines furnish the bulk of the southern and eastern pole
timber. To qualify as a pole, the tree must be very straight with
only a few small branches. It must have at least a 10-inch DBH
and 35 feet of relatively clear trunk to a 7-inch top diameter.
Pole identification and valuation is difficult. Generally, a
stand must consist of a good proportion of large, straight, well
pruned trees to be considered for a pole cut.
SMALL SIZED PRODUCTS--CUBIC FEET OR CORDS
The volume of small trees, usually sold for pulpwood, is
expressed in cords. A standard cord, or rough cord, is equivalent
to a stack of wood measuring 4' x 4' x 8' or 128 cubic feet.
However, much of a 4' x 4' x 8' stack is wood, bark, and air
space. The actual wood contained in a 4' x 4' x 8' stack is
approximately 90 cubic feet. Volume tables can be used to
approximate the cubic foot content and, consequently through
conversion, the cord content of an individual tree. The table
figures can be general or specific regarding tree species and the
size criteria used to develop it. In Table 2, the cubic foot
volume is expressed in terms of diameter at breast height in
inches, and total tree height in feet. This volume table was
developed for use with slash pines in north Florida.
To use the table, locate the diameter of the tree in the
column on the left. Read across until you reach the column that
represents the total height of the tree. For example: an 8-inch
DBH tree with a total height of 70 feet will yield 11.805 cubic
feet. The cubic feet divided by 90 results in the volume in terms
Another, but less accurate, way to approximate the pulpwood
yield in cords is by using Table 3 (Smiley, W. L. 1969).
Table 2. North Florida slash pine cubic foot volume based on total
tree height in feet and DBH in inches
Total Height (feet)
20 30 40 50 60 70 80 90 100
Cubic foot = -.976 + .002853*(d**2)*h
Specifications: location -- North Florida
tree height -- total
minimum height -- 16 feet to a 4-inch dob
number of trees -- 333
r-squared -- 99.1
authors and date -- Cooper and Olson, 1958.
Table 3. Number of trees of different diameters required to
make a cord.
DBH in Inches # Trees/Cord
LARGE PRODUCTS -- BOARD FEET
The volume of large trees for sawtimber, poles, or plylogs
is expressed in board feet or the equivalent of 1" x 12" x 12"
units of lumber that can be cut from a tree.
To estimate the number of board feet in logs of different
sizes, log rules are used. A log rule is a statement, either in
the form of a printed table or as marked on a measuring stick,
of the estimated board feet of lumber that can be sawed from
logs at various lengths and diameters.
Board foot products in Florida are normally estimated by
the Scribner or the Doyle log rule. Scribner is the most
commonly used for pine sawtimber, poles, and plylogs, while
Doyle is more commonly used for hardwood sawtimber and veneer.
The Scribner rule is probably fairest for buyer and seller of
southern timber, where most of the timber cut would be logs
smaller than 20 inches in diameter. Similar to the cubic feet
volume tables, board foot tables have been developed for speci-
fic locations and tree species. Table 4 is a general Scribner
board foot volume table constructed from diameter and usable
16-foot log size criteria. The table is used in the same manner
as the cubic foot table previously discussed, with one excep-
tion. For exceptionally tall, slender trees, add 10 percent of
the given volume and deduct 10 percent of the given volume for
stocky, tapered trees.
Table 4. Scribner scale board foot volume table by diameter at breast
height and number of usable 16-foot logs.
Number of 16-foot Logs
1 1U 2 22 3 32 4 41 5 51 6
10. 28 36 44 52
11. 38 49 60 67 74
12. 47 61 75 85 95 100 106
13. 58 76 94 107 120 128 136
14. 69 92 114 130 146 156 166
15. 82 109 136 157 178 192 206
16. 95 127 159 185 211 229 247
17. 109 146 184 215 246 268 289
18. 123 166 209 244 280 306 331
19. 140 190 240 281 322 352 382
20. 157 214 270 317 364 398 432 459 486
21. 176 240 304 358 411 450 490 523 556
22. 194 266 338 398 458 504 549 588 626
23. 214 294 374 441 508 558 607 652 698
24. 234 322 409 484 558 611 665 718 770
25. 258 355 452 534 617 678 740 799 858
26. 281 388 494 585 676 745 814 880 945
27. 304 420 536 636 737 811 886 959 1032
28. 327 452 578 686 795 877 959 1040 1120 1190 1261
29. 354 491 628 746 864 953 1042 1132 1222 1306 1389
30. 382 530 678 806 933 1028 1124 1224 1325 1421 1517
31. 411 571 731 871 1011 1117 1223 1328 1434 1541 1648
32. 440 612 784 936 1089 1206 1322 1432 1543 1661 1779
33. 469 654 838 1001 1164 1289 1414 1534 1654 1783 1912
34. 498 695 892 1066 1239 1373 1507 1636 1766 1906 2046
35. 530 742 954 1141 1328 1473 1618 1757 1896 2044 2192
36. 563 789 1015 1216 1416 1572 1728 1877 2026 2182 2338
A more recent and quite common way of purchasing forest
products is by weight. This measure tends to add another level
of confusion for many landowners who are not familiar with the
forest products industry.
As among people, the weights of similarly sized trees will
vary. Consequently, the weights of cords and board feet will
vary from species to species, seasons and location of harvest,
differences in growth rates, and the length of time between
harvesting and weighing in at the mill or scale site. Table 5
shows the differences in weights of cords among species and the
difference between air-dried and green weight of a cord of the
same species. Average weight conversions for the most common
forest products are listed in Table 6.
Table 5. Average weights of a standard cord (128 cubic feet)
of pine pulpwood for various species
Table 6. Weight conversions for common forest
southeastern United States
products in the
--------- pounds --------
128 cubic feet
128 cubic feet
5,350 5,000- 5,620
5,800 5,400- 6,075
Now that you know the basic concepts of measurements and
yield units you can begin to think about your wooded areas in
terms of what you have and how much there is of it.
STEP 1 -- Type Map
Prepare an inventory or type map of your land to define
each general land-use category. The land-use categories or
forest-types can be identified readily from an aerial photograph
of your property.
In most cases your county Soil Conservation Service (SCS),
Agricultural Stabilization and Conservation Service (ASCS), or
the Florida Division of Forestry will provide services to help
you construct the map similar to the one in Figure 2.
1" = 660'
Figure 2. Forest type map taken from aerial photograph showing
roads, property, and vegetation boundaries.
STEP 2 -- Determine Acreage
Determine the amount of acreage in each forest-type. A
plastic template called a "dot grid" facilitates this calcula-
tion. In most cases the ASCS, SCS, or Division of Forestry
Office will have instruments to help you calculate the acreage.
STEP 3 -- Select Sample Size
Decide how much of each type should be measured. The yield
of a stand is usually impossible to calculate by measuring each
tree. Typically, a portion of the stand is measured, and the
results of the measured trees are expanded to represent the
entire stand. The degree of sampling (the percentage of the
stand to measure) depends on the size and uniformity of the area
to be measured. When time is short or the forest large, the
owner may have to judge the yield of his whole stand by the part
he has time to measure. It is important to get a fair sampling,
neither better nor worse than the rest of the forest. In
general, the higher the value of the timber, the larger the
sample should be.
For measurement purposes, pine stands may be classified
into two categories -- planted stands (plantations) and natural
stands, or those that were established by natural conditions.
Generally, young planted stands, less than 20 years old,
are uniform in stocking (number of trees per acre), size (diame-
ter and height), and site or soil characteristics. If great
differences in any of the three characteristics are not obvious,
the yield of the stand may be estimated by measuring several
trees to calculate an average diameter and height.
As planted stands mature, obvious size differences among
the individual trees begin to show. Because of competition for
space, nutrients, moisture, and differences in growth rates of
individual trees, an older planted stand may begin to take on
characteristics of a natural stand.
The exact percentage of the stand that is needed for a
sample will vary according to the precision that is required,
the conditions of the stand, and the types of forest products
that may be present. If a stand has many trees that could be
sold for poles, a high value product, a higher percentage of the
stand should be measured.
General guidelines for the percentage of natural stands to
measure, or mature planted stands that are not uniform, are
listed in Table 7.
Table 7. Approximate percent of stand that should be measured
in relation to stand area
Stand Area (Acres) Percent Measured
11 25 33
26 50 20
51 100 10
101 500 5
STEP 4 -- Select the Best Inventory Method
There are many different inventory methods that may be used
to measure the sample areas. The appropriate method depends on
the characteristics and conditions of the stand. An experienced
professional forester is best qualified to judge the appropriate
method; however, there are some general selection criteria.
A strip cruise method may be useful for a high percent
cruise. To implement a strip cruise all the trees in a narrow
strip are measured. The number of strips that are run through
the stand depends on the width of the strip (usually one chain
or 66-feet wide), the length of the strip (usually determined by
the stand boundary), and the number of acres that are to be
For example, on 50 acres of mature pine with several
different sized trees the recommended minimum area to sample is
20 percent or 10 acres. The equivalent of one strip 66-feet
wide by 6,600-feet long must be measured. The property bounda-
ries may not accommodate a strip 6,600-feet long; therefore, it
will be necessary to run several strips on uniform spacing that
will equal the distance needed. Strips should be located to run
with the slope; that is, if the land slopes from north to south
the lines should run from north to south.
In large stands composed of relatively small sized trees
the fixed area plot is used. The fixed area may be circular or
square, but the size of the plot, in terms of area, depends on
the uniformity and age of the stand, and the amount of time it
takes to locate plot centers. Obviously, the larger the plots,
the fewer needed to measure a given area. The plot size that
generally includes 8 to 15 measurement trees is the best size to
use. Table 8 shows dimensions for different sized plots.
Table 8. Dimensions of square plots and circular plots in
relation to plot area
Area Square Plot Dimensions Circular Plot Radius
acre -------------- feet --------------
1 208.7 117.8
1/2 147.6 83.3
1/4 104.4 58.9
1/5 93.3 52.7
1/10 66.0 37.2
1/20 46.7 26.3
1/50 29.5 16.7
1/100 20.9 11.8
On 50 acres of planted pines that are relatively small and
uniformly spaced the recommended sample area is 10 percent or
five acres. Using 1/20-acre plots, 100 plots must be measured
to equal five acres of sample area. These plots must be uniform-
ly located across the entire 50 acres in order to get a fair
STEP 5 -- Tally the Plots
Two types of forms may be used to record the trees that are
measured in the sample plots. Examples of these forms are shown
in Figures 3 and 4.
The dot notation is a convenient way to record the number
of trees measured. This system is illustrated in Figures 3 and
4. One dot represents one tree in a particular diameter and
height category. Additional trees in the same category are
represented by additional dots until a square is formed by the
four dots -- this cluster represents four trees. The fifth tree
is represented by one line connecting two of the four dots. The
line connecting other dots in the cluster is used to record
additional trees until a square is formed by the lines. The
square, which is a result of four dots and four lines, repre-
sents eight trees in that category. Diagonal lines, forming an
"X" in the box, represent 10 trees. Additional trees in that
category are recorded using the same system to begin a new
SAMPLE PULPWOOD TALLY SHEET
Total Height (feet)
20 30 40 50 60 70 80
Figure 3. A sample pulpwood tally sheet with trees measured by
DBH and total height and recorded using a dot
SAMPLE SAWTIMBER TALLY SHEET
Number of 16-foot Logs
Figure 4. A sample sawtimber tally sheet
DBH and number of 16-foot logs
with trees measured by
using a dot notation
STEP 6 -- Summarizing Sampling Records
To summarize the sample measurements a summary table is
constructed from the information on the tally sheet and a volume
table. A summary table must be made for each separate product
that was measured in the sample plots. Figure 5 represents a
summary table for the pulpwood tally sheet shown in Figure 3. A
blank tally sheet, with the addition of a "sub-total" column,
may be used.
Total Height (feet)
20 30 40 50 60 70 80
8 13.506 31.64 81.54
10 62.616 159.46 290.556 379.90 655.44
Figure 5. A summary sheet indicating cubic feet volume for
each size category of trees measured in the sample.
The number in the first size category (6-inches DBH and
20-feet total height) is a result of multiplying the number of
trees in that category (2) by the number of cubic feet that a
tree of that size can be expected to yield. The cubic foot
estimate of one tree 20 feet tall and 6 inches in diameter
(1.078) is found in Table 2. Therefore, the estimated volume of
the trees in the sample that fell into the 6-inch DBH and
20-foot height category is:
Number of trees
in size class Volume/tree Volume/size class
2 X 1.078 cu. ft. = 2.156 cu. ft.
Each block in the table is calculated in the same manner
until all volumes for all size classes or categories have been
entered into the table. The cubic foot volumes are then summed
across the page by DBH class, or down the page by height class.
In this particular example the category volumes were summed
across the page first and then down the sub-total column to give
the total volume obtained from the sample.
STEP 7 -- Convert Sampling Estimate to Cords
The total cubic feet which resulted from the sample measure-
ments should be converted to cords by dividing the total by 90
cubic feet. In this example the number of standard cords in the
3,490.87 cu. ft. 90 cu. ft./cord = 38.787 cords in sample.
STEP 8 -- Convert to Cords/Acre
Suppose the measurements represent a five percent cruise of
a 30-acre stand of planted slash pine. Assuming this, the
actual area measured was .05 x 30 acres or 1.5 acres. There-
fore, the cords in sample (38.787) the acres in sample (1.5)
equals the estimated cords per acre (25.858 in this example).
STEP 9 -- Calculate a Market Value
As with any commodity the market value will vary considera-
bly based on the amount of the product to be sold, the season,
the accessibility of the forest, distance to the mill, and the
terms of the individual sales contract. Monthly price and
markets reports are published in the School of Forest Resources
and Conservation Extension Update Newsletter. Also, current and
historical price information is available through the IFAS-VAX
computer network system which can be accessed from many county
extension offices. While the stumpage prices shown
in these references do represent actual sales, keep in mind that
individual sales may bring higher or lower prices.
To convert your estimated cords per acre to actual dollars,
select a stumpage price that appears reasonable for your local
area. Multiply the estimated cords per acre by the stumpage
price. In this example $25.00 per cord price was selected;
therefore the stumpage value (money paid to you as the trees are
standing in the forest) is:
25.858 estimated cords/acre x $25.00 estimated price/cord =
Now that you see the relative value of your forest crop
keep in mind the following points:
1. The exercise you conducted was crude, at best, and it may
not be an accurate assessment.
2. There may be other volume tables which you are not aware of
that more closely represent the amount of wood on your
3. You may have selected an inappropriate sample size.
4. The terms of your individual sales contract and the condi-
tions of your forest may prevent your selling price esti-
mate from being realistic.
Because timber investments do involve considerably longer
turnovers, as compared to other agricultural commodities, many
individuals do not experience frequent sales. Consequently,
many landowners may not be aware of the value of their forest.
The purpose of this exercise was to inform you of the
complexities involved in trying to set values on your forestry
investment. Forestry is a business and should be treated as
Anonymous. 1944. Florida Farm Forestry. Bulletin 14. Florida
Forest and Park Service. Tallahassee. 33 pp.
Anonymous. 1975. How to Market Your Timber for More Money. Coop.
Ext. Pub. 1805. LSU Coop. Ex. Service. 12 pp.
Bryan, M.M. 1958. Measuring and Marketing Farm Timber. Farmers'
Bulletin No. 1210. For. Ser. U.S.D.A. Washington, D.C. 33
Fisher, R.F. et.al. 1979. Forest Management for Small Owner-
ships. Cir. 447. Dept. of For. SFRC, IFAS, Univ. of FL,
Gainesville. 35 pp.
Graeber, R.W. 1942. Four Steps in the Management of Farm Woods.
Ex. Cir. 260, N.C. State College of Agr. and Engineering
Raleigh. 7 pp.
Mark, G.G. and R.S. Dimmick. 1971. Managing the Family Forest.
Farmers' Bulletin No. 2187. For. Ser. U.S.D.A. Washington,
D.C. 61 pp.
McGregor, W.H.D. 1954. Flatwoods Farm Woodland Improvement
Pays. Cir. 125. S.E. For. Ex. St. Lake City Res. Center,
For Ser. U.S.D.A. 11 pp.
Rockwood, D.L. 1982. Unpublished) Measuring and Selling Your
Timber. Dept. of For. SFRC, IFAS, Univ. of FL., Gaines-
ville. 8 pp.
Smiley, W.L. 1969. Forest Farming. Cir. 459 (Rev.) Div. of
Agric. University of Arkansas. 67 pp.
Staley, L.E. (no date) Growing and Marketing Pulpwood. Bulletin
12. Florida Forest and Park Service. Tallahassee. 27 pp.
This publication was promulgated at a cost of $446.30 or 37 cents per
copy to provide information on identifying and measuring forest products.
COOPERATIVE EXTENSION SERVICE, UNIVERSITY OF FLORI-
DA, INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES, K. R.
Tefertlller, director, In cooperation with the United States Department JIFAB
of Agriculture, publishes this Information to further the purpose of the
May 8 and June 30, 1914 Acts of Congress; and Is authorized to pro-
vide research, educational Information and other services only to indi-
viduals and Institutions that function without regard to race, color, sex or national ori-
gin. Single copies of Extension publications (excluding 4-H and Youth publications) are
available free to Florida residents from County Extension Offices. Information on bulk
rates or copies fdr out-of-state purchasers Is available from C. M. Hinton, Publications
Distribution Center, IFAS Building 664, University of Florida, Gainesville, Florida
32611. Before publicizing this publication, editors should contact this address to deter-