All trees are grown to conform to certain nursery specifications, these can be rather ambiguous. This chart will give some guidance, but we are also here to help and advise.
Standard trees are measured in girth, which is the circumference of the trunk measured one metre from ground level. The girth of the tree gives a good indication of the maturity of the tree. Feathered and multistem trees are measured in heights.
The girth to height ratio can vary between species, this chart is an approximate guide to tree sizes.