“An expert knows all the answers…if you ask the right questions.” –Levi Strauss
Anyone seeking to improve the condition of their trees and property must adopt a questioning attitude. By asking questions, one can arrive a solution that is good for both tree and owner.
But like all living things, trees have unique needs as they age. A very young tree will require pruning strategies that are quite different than an old shade tree.
Young Trees
How you prune a young tree determines its shape in old age. Like a skeleton, the tree’s trunk and limb structure is the map of its future growth patterns. Fortunately, young trees tolerate heavy pruning, so aggressive restructuring of a tree is possible. Ask “What do I want this tree to look like when it is 80 feet tall?” Thinning closely-spaced lateral limbs will also improve the overall shape and appearance of the canopy. Ask “Which limbs can be removed to form a scaffold-like appearance in the tree structure?”
Another necessary question “Is the trunk well defined and formed straight? Does it grow in a graceful and pleasing way?” Since many structural problems develop later in life from poorly-formed trunks, young age is the right time to correct the trajectory of the tree’s main stems. “Are there competing leaders? Can the removal of multiple stems help this tree?” Your tree care professional can help you decide if this kind of pruning can help.
Medium-Aged Trees
This period of growth is a time to start shaping the overall canopy so that the tree can grow into a significant tree worthy of the landscape. Medium aged trees begin to encroach into our everyday outdoor activities. Ask “what obstacles in the landscape may conflict with this tree someday?” And “which low limbs must be removed completely before they get too big?” These questions will help you decide which limbs need to be removed prior to becoming problems. This is especially true of aggressive limbs that interfere with under story clearance and other landscape features.
This is also the time when tree canopies become thick with dense foliage. By asking “are there any branches that are crossing, rubbing, or interfering with other limbs,” you will prevent the tree from self-wounding. You should also ask “Is the canopy too dense for under story plants?” And “am I satisfied with the amount of sunlight getting through the tree?”
Medium age is also a good time to shape outer and inner branches to opening up your line of sight. Ask “What is behind this tree, of which I would like to get a better view?”
Mature Trees
In a perfect world, problematic live limbs growing on a mature tree would have been removed long before the tree attained a considerable size. But often a tree owner inherits a tree that is in need of some catching-up in the pruning department. Generally, one should seek to minimize the amount of live wood removed from a mature tree. So when looking at what must be pruned, the question is “how much can I take off from this tree and still accomplish my goal?”
The most common needs for live-branch removal is for building clearance and sunlight penetration. Ask “What is the least amount I can remove?” or “Can I remove this big limb and not damage the tree’s health?”
When surveying your mature tree’s canopy, always ask “Do I see any limbs or branches that are dead? Are there any that seem to have no twigs?” Some limbs may look alive, but are in the process of decaying. A good question to ask is “Are there any limbs that have strange growths, mushrooms, or discolored areas on the bark?”
Removal of dead or decaying limbs is an important and standard service for mature trees. All mature urban trees will require this kind of pruning on a regular basis, especially those over driveways, sidewalks, and structures.