Testing Decay in Trees with Resistance Drill!

There are a few ways to test for decay in trees. A resistance drill, or Resistograph, can be used to drill into the wood and measure the strength in real time. The drill measures the resistive forces that the wood pushes back on the drill bit, and records those on a graph. You can decipher these graphs to get a better idea of where the decay in the tree is.

This large Tulip Tree (Liriodendron tulipifera) had a large wound and cavity in it's base that likely originated from an accidental construction injury many decades ago. If a large wound occurs in the trunk of a tree, it can be difficult for the tree to compartmentalize the wound. This tree has been trying to close of the wound for many decades, but is ultimately losing the battle. We estimated the age of this tree to be about 130 years old, and the height is about 100ft.