Tree Care calculators
Tools for arborists and tree crews: green log weights by species, rigging shock loads, and trunk-formula appraisal. Every page shows its formula and says what the model leaves out.
- Log Volume CalculatorSmalian’s formula gives cubic volume as the average of the two end areas times the length: 0.005454 × (D₁² + D₂²) ÷ 2 × length, with diameters in inches and length in feet.Inputs: Small-end diameter, Large-end diameter, Log length
- Log Weight CalculatorA green white oak log 20 inches across and 8 feet long weighs roughly 1,100 pounds; weight is volume times the green density for the species.Inputs: Species, Average diameter, Length
- Lowering Wraps CalculatorThe capstan equation says the load equals the holding force times e raised to the friction coefficient times the wrap angle, so each extra wrap multiplies your holding power.Inputs: Rope tension on the load side, Holding force you can safely apply, Friction coefficient of rope on the device
- Mulch Volume CalculatorMulch volume is bed area × depth ÷ 12 in cubic feet, and one cubic yard covers about 108 square feet at 3 inches deep.Inputs: Bed shape, Length, or diameter of a round bed, Width
- Rigging Point Load CalculatorThe force on a block or anchor is the vector sum of the two rope tensions: with equal tensions T it equals 2 × T × cos(half the angle between the legs).Inputs: Load on the rope, Dynamic factor, Holding-side tension as % of load-side
- Rigging Shock Load CalculatorPeak force from a dropped load is F = W + √(W² + 2·W·h·k), where h is the free-fall distance and k the rope stiffness; even a short drop can load a line several times the weight.Inputs: Weight of the piece, Free-fall distance before the line loads, Rope length in the system
- Tree Appraisal CalculatorThe trunk formula scales a nursery tree's cost by trunk area, so value = trunk area × unit nursery cost per square inch, less depreciation for condition and limitations, plus added costs.Inputs: Trunk diameter of the tree to be replaced, Replacement nursery tree trunk diameter, Unit nursery tree cost comes from
- Tree Height CalculatorTree height = distance × (tan of the top angle − tan of the base angle), with a base reading below eye level entered as negative.Inputs: Horizontal distance to the trunk, Clinometer scale, Reading to the top
In the works
- DBH and multi-stem DBH
- Tree protection zone
- Felling hinge guide
- Label-rate dosing helper