The software is accurate to 10cm on tree height and 1cm in diameter of trunk, said Marcus Bellett-Travers, technical developer at Trees Project.
"How Big is This? Tree has been developed for the arboriculture market," he said. "You can measure diameter at breast height.
"You can work out tree height and the height and width of the canopy, how much wood there is in the tree and whether the tree would hit a building if felled."
Using a properly calibrated camera, the user transfers the image to his or her PC. The software is modelled on another package called How Big is This?, which allows users to work out the size of objects without using tape measures or surveying tools.
"It gives quick and simple measurements without the need for expensive equipment or a bulky tripod. It is not a professional surveying tool but is accurate if used properly."
The software costs £29.99 including VAT, with a £5 discount for Horticulture Week readers. Contact firstname.lastname@example.org