Revision of Arboriculture standards are ongoing, one being the crossing branch. While Duncan Slater PhD‘s science on the fork/crossing branch structure changes everything, it is evident that arboriculture is behind the curve.

       Everywhere Des Moines Tree Services implement practices based on old research about crossing branches. In the experience of the Arboriculturist at Olson Tree Care, the bad crossing branch is only evident about 20% of the time. 

       Years ago ISA Certified Arboriculturist Chris Olson (WE12363A) had this intuition now given words by science and research. At the time Olson Tree Care received feedback from other Des Moines Tree Services calling it the “natural selection of trees” referring to branch selection and dominance. This conclusion was deducted by intuition, field study and Tree Service repetition.

       Two other findings of Olson Tree Care in Des Moines, Iowa that are opposed to industry standards are the removal of 30% of a trees canopy every 2 years and the removal of up to 50% of the live crown ratio.

       These two standards are ridiculous and far too aggressive. Like the crossing branch scenario, it may be true for a percentage of the time but the majority of the time, removal of that much of the tree is detrimental to tree health.

       Revision in Arboriculture is ongoing. One day we will be more advanced in Tree Care eliminating “societal desires”, and caring for trees as they care for themselves.

       A future example of proper Tree Care? 

       A proper branch removal would be a heading cut in fall allowing translocation of resources for the winter and following growing season. Then a proper Branch Protection Zone (BPZ) cut removing the headed branch the following winter. For a more advanced description review our article on Natural Branch Occlusion.