Free Trees & Forestry tool
Free Trees & Forestry toolTree Value Calculator
The Tree Value Calculator determines landscape tree monetary appraisal value using the Council of Tree and Landscape Appraisers (CTLA) trunk formula method. A stick of timber is worth what the scale says it contains, minus what it costs to get it to the landing. Measure the small end inside bark, count the logs, and this calculator runs the Doyle rule, converts to MBF, then stacks your price per thousand against harvest cost to show the net value of one tree.
Tree Value Calculator: result
Enter your values. Results update instantly.
72.800.432 MBF × $400 per MBF.Enter your values. Results update instantly.
20/MBF.Enter your values. Results update instantly.
20.96Gross value minus harvest cost, per tree.At a glance
- What it does: Scales logs by the Doyle rule from small-end diameter and length, then nets price against harvest cost.
- Who it is for: Made for landowners, students and small-woodlot sellers checking a tree's worth before a sale.
- Typical result: Returns board feet, MBF, gross value, harvest cost and the dollars left per tree in one pass.
How to use the tree value calculator
- Measure the small-end diameter inside bark at the top of each log: across the narrow face, rounded to the half inch the rule expects. prefill →
- Enter the log length in even feet (16 ft is the standard sawlog; standard practice rounds short logs down, not up) and how many logs of that length the tree yields. prefill →
- Set the price: stumpage (you sell standing) or delivered (you sell logs at the mill). Never mix the two conventions in one comparison.
- Enter harvest cost per MBF (marking, felling, skidding, loading, hauling) or 0 if the buyer absorbs it; the net row then shows what the tree is actually worth to you.
- Check that the price quote names the same log rule the volume was scaled under (Doyle here), and deduct defect separately: no rule scales rot.
Tree Value: the formula & its source
The Doyle log rule, the most widely used rule for selling standing timber in the eastern US:
board feet per log = (d − 4)² × L ÷ 16 (d = small-end diameter inside bark, inches; L = log length, feet)
Volume stacks across logs, MBF is thousand board feet, and value falls out linearly:
total BF = BF per log × number of logs · MBF = BF ÷ 1,000
net value = MBF × price per MBF − MBF × harvest cost per MBF
The fixed 4-inch subtraction is Doyle's sawkerf-and-slab allowance: it stays constant while waste shrinks with log size, which is exactly why the rule under-scales small logs and over-scales large ones.
| Symbol | Meaning | Unit | Typical range |
|---|---|---|---|
d | small-end diameter inside bark at the log top | in | 4–36 in |
L | log length scaled to even feet | ft | 8–40 ft |
n | logs of that length the tree yields | count | 1–10 |
BF | board feet produced, 144 in³ each | board feet | 10–1,000 |
P | price per thousand board feet | $/MBF | 0–3,000 |
C | harvest cost per thousand board feet | $/MBF | 0–500 |
Compare Doyle small-log underscaling against the International 1/4-inch recovery standard in our timber log rules and board foot volume guide.
Tree Value: worked example
Worked example: three 16-foot logs, 16 in small end, $400/MBF stumpage, $120/MBF harvest cost. BF per log = (16 − 4)² × 16 ÷ 16 = 144 × 1 = 144 BF. Total = 144 × 3 = 432 BF = 0.432 MBF. Gross = 0.432 × 400 = $172.80; harvest cost = 0.432 × 120 = $51.84; net = $120.96 per tree. Note the square law at work: stepping the small end from 16 to 20 in takes the per-log volume from 144 to 256 BF: diameter buys board feet far faster than length does.
Example B: small log under Doyle
Example B: a 10-inch small end. Three 16-foot logs with the top measuring 10 inches inside bark scale to (10 − 4)² × 16 ÷ 16 = 36 BF each, 108 BF for the tree, or 0.108 MBF. At $400/MBF that is $43.20 gross. Notice what the fixed four-inch deduction did: it removed about 44 % of the geometric volume on this log, against roughly a sixth on the 16-inch one above. Doyle is hardest on exactly the small timber a young stand produces, so ask which rule a buyer will scale on before quoting either figure.
Field method
Measure the small-end diameter inside bark at the top of each log, across the narrow face, rounded to the half inch the rule expects. Lengths scale in even feet (standard practice rounds a 15 ft 7 in stick down to 14 ft rather than up), and mixed 8- and 16-footers must be counted separately instead of averaged. Then settle the price: stumpage when you sell standing, delivered when logs go to the mill, never the two at once. Harvest cost per MBF follows, covering marking, felling, skidding, loading and hauling, or zero when the buyer absorbs them. Check that the quote names the same rule used here.Photograph the log ends when a scale might be disputed, since a picture of the small-end measurement settles most arguments before they ever start.
From one log to the whole sale
Board feet stack linearly (three equal logs simply treble one), but the dollars do not, because defect, grade and haul distance all intervene between the rule and the bank. The net row is where forestry becomes economics: the same 432 board feet is a windfall or a loss depending on who pays for the skidder. Volume itself rides the square of the small-end diameter, so a crop tree grown from a 16-inch top to a 20-inch top returns about 78 % more board feet on an identical log count. That figure is the arithmetic behind leaving a stand one more rotation, and it is why whole-stand sales exist: a buyer absorbs harvest cost in exchange for a discount.
Instrument error
A log rule is arithmetic, not an appraisal. It measures sound wood under ideal geometry while every real log departs from that ideal: rot, stain, sweep and breakage have to be deducted by eye, and grade swings price several-fold at unchanged volume. The rule named in the price quote must match the rule used here: Doyle, Scribner and International volumes for one log can differ by a fifth or more in the sizes people actually sell. Measuring the large end instead of the small one, or measuring outside bark, inflates the result through the very square law the rule is built on, and the error repeats on every log in the tree.
Common blunders
Doyle's fixed four-inch kerf deduction hits small logs hardest: it removes about a sixth of a 16-inch log and nearly half of a 10-inch one, so the rule systematically short-changes young timber. Pairing a stumpage quote with a delivered cost double-counts the harvest bill, while rounding a 15 ft 7 in log upward bills the buyer for wood that is not there. A price quoted per board foot but entered per MBF moves the answer by three orders of magnitude. And scaling sound volume on a hollow tree simply hands the difference to whoever is buying.
Worked field example
Three 16-foot logs with a 16-inch small end: BF per log = (16 − 4)² × 16 ÷ 16 = 144, so the tree scales to 432 BF, or 0.432 MBF. At $400/MBF stumpage the gross is $172.80; at $120/MBF harvest cost the deduction is $51.84, leaving $120.96 net per tree. Step the small end to 20 inches and the per-log volume becomes (20 − 4)² = 256 BF (78 % more from the same three sticks), which is why a crop tree left to grow past the first sawlog rotation pays better than one cut early at a smaller diameter.
Unit systems
The log trade runs imperial end to end: diameters in inches, lengths in feet, volumes in board feet or MBF, prices per MBF. A board foot is 1 × 12 × 1 inch (144 cubic inches), and that is the unit every price quote rests on. Metric crews convert at the pencil rather than at the keyboard: 2.54 cm to the inch and 0.3048 m to the foot, then work back to the figures the rule expects, because no metric branch of Doyle exists. Price and cost share a currency unit, so quoting one per MBF against the other per board foot quietly misplaces the decimal by three places.
What your tree value result means
MBF (thousand board feet) is the currency unit of the log trade, and the net row is where forestry becomes economics: the same 432 BF is a windfall or a loss depending on haul distance and stumpage terms. Because Doyle scales on (d − 4)², value grows with the square of the small-end diameter; a 20-inch small end returns 78 % more board feet than a 16-inch one on the same log count and length, which is why letting crop trees grow past the first sawlog rotation pays.
The gap between gross and net also explains why whole-stand sales happen: a buyer absorbs the harvest cost, discounts it from the stumpage price, and prices the risk of unsold logs out of the deal.
How to read the output:| Result range | What it means | What to do next |
|---|---|---|
| $120.96 net | gross minus harvest on the worked tree | Compare against a forester's cruise before selling |
| 0.432 MBF | 432 board feet put into pricing units | Quotes are per thousand, never per foot |
| 20 in small end | 78 % more volume than a 16 in top | Growing on pays better than cutting early |
| Doyle, small logs | fixed four-inch deduction bites hardest | Confirm the buyer's rule before comparing quotes |
| Cost row at zero | buyer absorbs the harvest | That figure is a delivered price, not stumpage |
Estimate stand cross-sectional stocking density per acre using our forest basal area calculator.
Common mistakes with the tree value
- Mixing a stumpage quote with a delivered cost: Pick one convention and say so: delivered prices already carry felling and haul, so subtracting harvest again double-counts the bill.
- Scaling the large end or measuring outside bark: Read the top of the log inside bark across the narrow face, since the rule assumes exactly that geometry on every stick.
- Rounding short logs up to the next foot: Standard scaling rounds down: a 15 ft 7 in log becomes 14 ft, and rounding up bills for wood the mill never receives.
- Comparing Doyle volume with an International-rule quote: The rules disagree by a fifth or more at common sizes, so confirm which rule set the price was scaled under first.
- Quoting gross value as what the tree is worth: Enter harvest cost per MBF so the net row shows the dollars that reach you after marking, felling, skidding and hauling.
Limits of the tree value calculator
A log rule is arithmetic, not an appraisal. It measures sound wood volume under ideal geometry: defect, rot, stain, sweep, and breakage must be deducted by eye, and grade (veneer vs pallet vs pulp) can swing price several-fold at identical volume. The rule named in the price quote must match the rule used here: Doyle, Scribner, and International volumes for the same log can differ by a fifth or more in the sizes where people actually sell.
Doyle's fixed kerf subtraction systematically short-changes small logs (its four inches remove proportionally far more from a 10-inch log than a modern saw loses), so never use it to compare young vs mature stands, and when buying small-diameter timber ask which rule the seller scaled on. Standing-timber sales are also legally sensitive in many places: get the sale marked and cruised by a licensed forester before signing.
Forestry note from Dr. Dinesh A. Nagegowda, PhD: Calculating standing sawtimber value requires converting log dimensions into usable board feet using traditional log rules (Doyle, Scribner, or International 1/4-inch). In timber appraisal, the Doyle rule heavily underestimates small-diameter logs under 14 inches due to an excessive slab allowance, whereas the International 1/4-inch rule provides the most mathematically accurate estimate of true lumber recovery in modern sawmills.
Sources
- Purdue University Extension FNR-191, Doyle log rule tables (used for: the Doyle formula and the worked 16 in by 16 ft table entry)
- Virginia Cooperative Extension publication 420-085, log rule tables (used for: rule-matching guidance and comparison between log rules)
- University of Missouri Extension G5050, How to Measure Trees and Logs (used for: even-foot scaling and small-end-inside-bark measurement practice)
Cite This Calculator
For laboratory course reports, academic papers, or institutional protocols (APA format):
Tree Value: frequently asked questions
What is MBF?
Thousand board feet: the standard sales unit. A board foot is 1 in × 12 in × 1 ft (144 in³); 432 BF is 0.432 MBF. Prices are quoted per MBF so lots of different log sizes compare cleanly.
Why does Doyle under-report small logs?
Its 4-inch kerf-and-slab deduction is a fixed inch count, not a proportion: on a 16-inch log it removes about a sixth of the scaled volume, but on a 10-inch log it removes nearly half, far more than a modern saw loses. The International quarter-inch rule corrects this and is preferred where mills scale that way.
Stumpage or delivered price, which am I using?
Stumpage is what the standing tree is worth to you before harvest; delivered adds felling, skidding, loading, and hauling. Enter your harvest cost here and either convention works. The net row is comparable. Quoting one against the other without adjustment double-counts or ignores the harvest bill.
How do I price a whole standing tree?
Scale the merchantable logs (this tool), apply a local stumpage price for that rule and grade, deduct defect, and compare against a forester's cruise. Standing sales in most US states are subject to trespass and tax rules. A licensed forester marks the crop trees and papers the sale.
Found a number that does not match its source? Report a mistake. Corrections are published in place and the page date is updated.
A value here that won’t reconcile with its reference? Report a mistake.
Dr. Dinesh A. Nagegowda, PhD: Plant & Molecular Biology Editor
Dinesh is a plant molecular biologist and Chief Scientist at CSIR-CIMAP whose research runs through functional genomics, transcriptomics, metabolomics, and biosynthetic pathways in plants. He writes and…