Double bit axes can be used for felling trees, cutting logs, splitting firewood, or landscaping. The advantage of a double bit axe is that each side of the axe head can be designed with different thicknesses and widths. The most common design has one side thinner designed for cutting deeper into the trunk when felling trees, with the other side thicker to force fibers apart when splitting firewood. Double bit axes are one of the most versatile tools in your garage.