Spike's Calculators

# Swedish Log Volume Calculation

Measurement of log volume under bark - SDC's instructions for estimating timber volume.

All diameter measurements are measured under bark.

## Measuring log volume using top-butt diameter measurement

Top-butt measurement may be used for all tree species on logs with a top diameter of ≥ 3 cm and length ≤ 6.5 m
The diameter is measured 10 cm from each end of the log, with the exception of the butt end of a butt log, where the measurement is taken 50 cm from the end.

##### Formula used:
`V =  π ÷ 4 * L[cDl² + (1- c)Dt²]`
where:
V = the log volume in cubic metres
c = constant
Dt = small end diameter taken 10 cm from end of log
Dl = large end diameter taken 10 cm from end of log/ taken 50 cm from the end of a butt log

### Using Small and Large Diameters

Length of Log m
Small end diameter cm
Large end diameter cm

#### Results:

 Log Volume m³

#### Calculation

1. the log length in metres
2. top end diameter measured 10 cm in from top end of log in centimetres
3. butt end diameter measured 10 cm in from butt end of log or 50 cm butt end of a butt log

## Measuring log volume using top (small) end diameter measurement

Top measurement may be used on all tree species, regardless of diameter and length.
The top diameter is measured 10 cm from the top end of the log.

##### Formula used:
`V =  π ÷ 4 * L * Dt²`
where:
V = the log volume in cubic metres
Dt = the small end diameter measured 10 cm from the top end of log

### Using Small End Diameter

Length of Log m
Small end diameter cm

#### Results:

 Log Volume m³

#### Calculation

1. the log length in metres
2. top end diameter measured 10 cm in from top end of log

## Measuring log volume using mid-point diameter measurement

Mid-point measurement may be used on all tree species, regardless of diameter and length.

##### Formula used:
`V =  π ÷ 4 * L * Dm²`
where:
V = the log volume in cubic metres
Dm = the mid-point diameter

### Using Mid-Point Diameter

Length of Log m
Small end diameter cm

#### Results:

 Log Volume m³

#### Calculation

1. the log length in metres
2. diameter measured at the mid length of the log