Natural Target Pruning: a rule of thumb
The practice of natural target pruning makes use of the branch collar to identify the proper location to remove a branch. There is a three-cut process that must be used to remove branches in order to preserve the bark tissue and the branch collar.
- The first cut (marked A in figures below) is an undercut about 1/4 through the branch, made upward from the bottom of the branch, about 25 to 50mm further out than the collar.
- The second cut (marked B in figures below) is a downward cut just outside the undercut that actually removes the entire branch, eliminating the weight of the branch before making the final natural target cut.
- The third cut (marked C -D in figures below) is the natural target cut. The remaining portion of stub is removed with a cut made just outside of the branch collar tissue.
Why Target Prune
Current thinking states there are two extremes of the final cut to be avoided, namely ‘stub cuts’ and ‘flush cuts’
- ‘Stub cuts’ (those made beyond the line CD in the figures above) leave a large food source for parasitic decay fungi, which can then break down the trees natural defense barriers. Additionally the presence of the ‘stub’ prevents the complete closing of the wound through callus.
- ‘Flush cuts’ (those made within the line CD in the figures above) result in removing the site where the natural defense barrier of the tree would normally form and so expose the trunk itself, to the risk of decay.