The tree width, which dictates the width of the saddle and height of the gullet, is one of the most important factors when fitting the saddle, and can be tested easily by looking at the sweat pattern on the animal's back after work. A tree that is too narrow is more of a threat than one too wide, as it pushes the points of the saddle tree into the horse's back. This will often result in a hollowing if it persists for long periods of time. The sweat pattern will have even sweating along the panels, except for the points of the tree, which will cause round dry spots in the area of sweat, as a result from the pressure.