Sink or Source is a term used in arboriculture to describe how a branch responds in regards to how it provides or uses up sugars within the tree. When a branch is using up more than it produces, the tree will compartmentalize the branch at the union point at the main meristem. This is why when you look up the tree you will see that most of the lower branches are dead or declining because of inadequate sunlight filtration. Removal of these branches lets the sun and air through the tree and helps to invigorate the remaining foliage as well serving to protect what is under the tree from falling branches.
Here at Jacob’s Ladder Tree Tech, we use non-invasive climbing and rigging techniques when the tree is not a removal. This means the use of friction savers and blocks to protect the cambium layer of the tree. Cambium is the layer under the outer Bark that is responsible for tree growth and production. We use static rope climbing techniques instead of spurs or spikes that dig into the cambium and create potential entry wounds for disease.