Timber Rotation Age Calculator

Work out timber rotation age instantly with clear inputs, formula shown and shareable results.

About Timber Rotation Age Calculator

The rotation of maximum volume production is the age at which mean annual increment culminates, which is exactly where current annual increment falls to equal MAI. While CAI exceeds MAI the stand is still adding volume faster than its lifetime average and should be left; once CAI drops below MAI, growth is diluting the average and harvest is due.

Formula

Increment

MAI = standing volume / age; culmination occurs where CAI = MAI

Worked example

With the default values below, Timber Rotation Age Calculator returns Mean Annual Increment of 10.000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Standing Volumeminimum 0 m3/ha: 120 m3/ha
Current Stand Ageminimum 0.1 years: 12 years
Current Annual Incrementminimum 0 m3/ha/year: 14 m3/ha/year
Timber Priceminimum 0 per m3: 4,500 per m3

Results

Mean Annual Increment: 10.000
Current Annual Increment: 14.000
Rotation Guidance: Before culmination - keep growing
Standing Value: $540,000.00

Step by step

1Values used
2Increment
3Mean Annual Increment= 10.000
4Current Annual Increment= 14.000
5Rotation Guidance= Before culmination - keep growing
6Standing Value= 540,000.00

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax or fees or charges into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Is maximum volume the right rotation economically?

Not always. A financial rotation using discounted revenue and land expectation value is usually shorter than the maximum-volume rotation, because money tied up in standing timber has an opportunity cost.

How is CAI measured?

From repeated inventory of permanent plots, or from increment cores giving radial growth over the last few years converted to volume with a taper function.