The description of tree sizes is most often in terms of three broad height categories. Mainly the measurement of tree height is as the vertical distance between the base and the topmost branch; calculation is done by triangulation remotely from the ground.
A small tree is one that will reach a maximum height of no more than 25 feet at maturity. At the extreme, is the Dwarf Arctic Willow (Salix herbacea) which in nature grows to a height of only 2-3 inches at maturity. While medium-size trees tend grow to a height of 25 to 40 feet.
Besides, large trees are representative of the broadest category, achieving heights of 40 to over 100 feet. Extreme height is an accomplishment by Redwood trees (Sequoia sempervirens); the champion, growing in California. Hyperion and measures to stand 380 feet tall.
Furthermore, trees in the small category include both single and multiple stem species; medium and large trees are most commonly single stems. Whatever its potential height, each tree species goes through a life cycle of seedling, sapling and maturity with each cycle extending over some time period; and reaches maximum size (height, girth and canopy width) at maturity when additional growth all but ceases.
Generally, in speaking of tree size, we are referring to tree dimensions at maturity. Both the maximum size it attains, and the amount of time it requires to reach full size, are upon the tree’s genetic makeup. Assuming that growth conditions are ideal in terms of illumination, soil and water, for the tree.
Common Tree Measurements
Two other common tree measurements to describe trees: are girth and crown spread (width). Girth is the measurement around the tree trunk at a point of 4.5 feet above ground and it a manner to calculate the DBH (diameter at breast height). At that point there is no influence from the flare of the trunk. Small trees have a DBH of up to 14 inches; medium trees 15-19 inches, and large trees 20 inches or more.
In the nursery trade, we describe trees in terms of their caliper, which is the measure of diameter; and depends upon plant size made at a point 6-12 inches above the ground. Crown spread is a maximum horizontal measure of the tree crown in a diameter. In many species, the crown spread approximates the subsurface network of the tree’s roots. As, trees with multiple stems and/or irregular shapes are difficult to characterize in terms of girth and spread.
Selecting trees of appropriate mature size is important in long-term garden planning with the growth rate issue. A slow-growing tree which matures into a large tree can give many years of enjoyment before becoming too large. Also, moderate to severe pruning can maintain a favorite tree at a manageable height for an indefinite period. However, it is important to note that not all trees respond well to pruning to maintain a smaller stature.
Species in the TreeWorld inventory are described as being small, medium or large, and in addition, with the caliper measurements. If you need more information on tree sizes or another matter you can contact us!