Standing Timber Calculator
Estimate board feet for standing trees. Enter DBH (diameter at breast height) and merchantable height to get Doyle, Scribner, and International 1/4" estimates.
Single Tree Estimate
Enter DBH and merchantable height above.
Stand Cruise (Multiple Trees)
Add tree entries to estimate total stand volume. Use this for small woodlot cruises or before-sale timber estimates.
| DBH (in) | Height (ft) | Count | Doyle (BF) | Scribner (BF) | Int'l 1/4" (BF) | |
|---|---|---|---|---|---|---|
| Total | — | — | — | |||
How this calculator works
This tool estimates board feet in standing timber using three standard US log scaling rules applied to each tree's dimensions. It requires two inputs per tree:
- DBH — diameter at breast height, measured 4.5 feet above the ground on the uphill side of the tree, outside bark. Use a diameter tape (D-tape) for accurate readings.
- Merchantable height — the length of usable trunk from stump height to the first major fork, a 4-inch top diameter, or any defect that limits lumber production. Field measurement typically uses a clinometer or relascope from a fixed distance.
The calculator estimates small-end diameter inside bark (DIB) by subtracting 2 inches from DBH (a standard 1-inch-per-side bark assumption). Merchantable height is divided into 16-foot log sections. Volume is computed per section using each log rule's formula, then summed.
What is a timber cruise?
A timber cruise is a systematic inventory of trees in a forest stand to estimate total merchantable volume. Professional foresters use statistical sampling methods (fixed-radius plots, prism cruising, or point sampling with a Bitterlich relascope) to measure a representative sample of trees and extrapolate total stand volume per acre.
This calculator's stand cruise table is a simplified version: you enter each tree size class you observe and how many trees of that size exist. It does not apply statistical sampling theory — it is a direct sum of the entered trees. For woodlots up to a few acres where you can inventory every merchantable tree individually, this approach gives a reasonable estimate. For larger tracts or commercial timber sales, hire a licensed consulting forester.
How to use the stand cruise table
Click + Add Tree for each distinct tree size class. Enter the DBH (in inches), merchantable height (in feet), and how many trees of that size are in the stand. The table calculates board feet per tree and sums the totals across all three log rules. For a simple two-acre woodlot, you might walk the entire stand and tally every tree — entering 20" DBH / 48' height / 3 trees, then 14" DBH / 32' height / 12 trees, and so on until you have covered the stand.
Which log rule should I use?
Use whichever rule your buyer, state forestry agency, or timber sale contract specifies. In practice:
- Doyle — dominant in Appalachia and the Southeast for hardwood. Significantly underestimates small-diameter logs, which disadvantages landowners with mixed-size timber.
- Scribner Decimal C — used by the USDA Forest Service and standard in Pacific Northwest softwood markets.
- International ¼" — the most accurate rule across the full range of log sizes; common in the Northeast, Midwest, and Lake States for both hardwood and softwood.
Showing all three rules simultaneously helps landowners understand the range of possible outcomes before negotiating a timber sale price. → Full guide: Log Rules Explained
Limitations and disclaimer
These are estimates intended for planning and orientation — not for binding timber transactions. Actual recoverable board feet depends on log form factor (how cylindrical the tree is), taper rate, defects (rot, seams, crook, sweep), bark thickness variation, and the specific sawmill's kerf and recovery efficiency. For formal timber sales, hire a licensed consulting forester who will cruise the stand in person using proper sampling methods and act as your agent to ensure fair market value.
← Log Scale Calculator · How to Measure Logs · Log Rules Guide
Frequently Asked Questions
What is DBH in forestry?
DBH stands for Diameter at Breast Height — the standard tree measurement taken at 4.5 feet above ground level on the uphill side of the tree, measured outside the bark. It is the primary input for estimating standing timber volume and is universally used in timber cruising, forest inventory, and tree valuation across North America.
How do I measure merchantable height?
Merchantable height is the usable trunk length from stump height to the point where the log becomes too small, forked, or defective to produce lumber. Common cutoff points are: the first major fork, a minimum top diameter of 4 inches inside bark, or any defect (rot, severe crook, large seams) that would cause the log to be rejected. In the field, use a clinometer or hypsometer to measure this height in feet from a known distance.
Why does this calculator give three different board foot estimates?
The three values correspond to three different log scaling rules — Doyle, Scribner Decimal C, and International ¼-inch. Each uses a different formula that makes different assumptions about saw kerf and slab waste. Doyle consistently gives the lowest estimate (especially for small logs), Scribner is intermediate, and International ¼" typically gives the highest value and most closely reflects actual mill recovery.
How accurate is a standing timber estimate?
These are rough estimates intended for planning purposes only. Accuracy depends on how closely the calculator's bark deduction (2 inches) matches your actual trees, how uniform the stand is, and how complete your tree sample is. Actual recoverable board feet is further affected by log taper, sweep, crook, rot, and the specific sawmill's recovery efficiency. For formal timber sales, always hire a licensed consulting forester.
What is a timber cruise and how does the stand table work?
A timber cruise is a systematic sampling of trees in a forest stand to estimate total timber volume. The stand cruise table in this calculator lets you add multiple tree entries (different DBH and height combinations, each with a count) to tally the total volume for a group of trees. This mimics a simplified cruise — enter each size class you observe and its count to get a rough total volume estimate for the stand.
How does this calculator estimate diameter inside bark from DBH?
The calculator subtracts 2 inches from DBH (1 inch of bark per side) to estimate the small-end diameter inside bark (DIB) used in the log scaling formulas. This is a common default assumption. Bark thickness actually varies by species: thin-barked species like Yellow Birch may have only 0.3–0.5" per side; thick-barked species like mature White Oak may have 1.5–2" per side. For species-specific accuracy, measure actual bark thickness and adjust accordingly.
What should I do before selling standing timber?
Before selling standing timber: (1) get a cruise from a licensed consulting forester to establish an independent volume estimate; (2) get competitive bids from at least 2–3 buyers; (3) understand which log rule the buyer will use to scale the logs — Doyle can pay you significantly less than International ¼" for the same wood; (4) consider a timber sale contract with a licensed forester acting as your agent. Landowners who sell timber without professional guidance consistently receive below-market prices.