The size of the crown is linked to how well a tree grows, a larger crown size allows for larger foliage. Larger foliage provides a greater opportunity to capture the sun’s rays that allow the tree to grow. The crown size also affects the visual impression of the tree, which is important in parks and gardens.
When you measure the crown size, you measure both its height and its width. The width is often measured from several directions as it is seldom completely circular. Then take the mean value of the diameter of the crown. The crown height is the height from the lowest branches to the top of the tree.
In Arboreal Tree Height, you can measure both crown width and crown height. The easiest way is to first measure the height from the lowest branch to the top. Name the tree with that value and then press the back button twice at the bottom left and measure the height of the tree as usual. Then choose to measure the crown width and mark each side of the tree’s crown and then save the measurement. Now you have values for tree height, crown height, and crown width. Here is a movie about how it is done.
It is a good idea to measure the tree from another direction and take the average value of these measurements. You can see a summary of your measurements in the app and you can also export it as a csv file that can be opened in other apps, for example, Microsoft Excel