For larger trees, how deep should girdles be cut?

The recommended depth for girdles on larger trees is typically between 1 to 2 inches. This depth is crucial because it ensures that the cambium layer, which is responsible for the tree's growth and nutrient flow, is effectively disrupted. By cutting through this layer, you stop the movement of nutrients and water between the roots and leaves, leading to the tree's eventual decline.

Cutting too shallow may not effectively girdle the tree, allowing it to potentially recover. Conversely, cutting too deeply might risk damaging the surrounding bark and cause unnecessary harm to other potential layers of the tree, which can be counterproductive. Therefore, a depth of 1 to 2 inches balances effectiveness with health considerations for the tree's structure.