Fig. 1

Representation of the tree of a given diameter \({D}_{z}\) under the drag force \({F}_{wind}\) where \({H}_{w}-z\) is the lever arm at a given height \(z\) in the tree
Representation of the tree of a given diameter \({D}_{z}\) under the drag force \({F}_{wind}\) where \({H}_{w}-z\) is the lever arm at a given height \(z\) in the tree