In the USA, the diameter of the tree stand was measured at 4.5 feet above the ground, while the countries with the metric system, the diameter of the tree stand was measured at a height of 1.3 m from the ground surface. Diameter at other points along the trunk of the tree is often indicated by: d0,5h = diameter at half the height of the total; d0,1h = diameter at a high 0.1 total; d6 = diameter at a height of 6 m from ground level