| There has been much research data shared and | | | | of it falling on people is greater than we may |
| discussed that supports the idea that it is most | | | | think. Generally speaking, dead wood should be cut |
| beneficial to prune trees of all species in the | | | | back to where there is live tissue and in a way |
| dormant season (winter). So most practicing | | | | that promotes the growth of live tissue over the |
| arborists will agree that winter is the best time to | | | | wound. A certified arborist will know where best |
| prune. There are many reasons for this, but since | | | | to make a cut to promote the fastest healing. |
| there is such an overwhelming consensus on the | | | | Another reason to prune trees is perhaps the |
| matter I think this discussion should be more | | | | most misunderstood of all of the reasons. That is |
| about how the trees should be pruned. | | | | to reduce the risk of a tree failing due to wind |
| Pruning Trees | | | | exposure. It is true that some trees become |
| Probably the most common reason to trim or | | | | more prone to breakage as they grow, but the |
| prune a tree is to remove branches that are in | | | | reasons for this are not well understood by many |
| the way of something. Maybe satellite reception is | | | | who prune trees. It would take too much time |
| poor due to an obstructing limb, or a view is | | | | and space to explain fully, but in general leaders |
| obstructed, a light is covered, a branch is rubbing | | | | and branches are more or less prone to failure as |
| a building, etc. When pruning to mitigate these | | | | a result of their angle of growth from the parent |
| issues, we are most often removing live limbs | | | | stem. Steep angles - sometimes referred to as |
| from a tree. When we do this we should take | | | | co-dominant - have a greater potential for failure. |
| care to make cuts that will heal and leave a | | | | Safety pruning should be focused on the reduction |
| proper terminal branch to the leader that is cut. It | | | | or elimination of these kinds of branches and |
| is not acceptable to simply cut at a convenient | | | | leaders. Simply taking the tops off of leaders |
| place that achieves the clearance that we are | | | | does not achieve safety for the same reason |
| seeking. In fact, cutting at improper points on a | | | | mentioned above in the case of pruning live limbs |
| branch will often encourage the overgrowth of | | | | for clearance. The eventual grow-back of the |
| "water sprouts" that will soon make the clearance | | | | leader in the form of water sprouts just makes |
| or obstruction worse than when we began. | | | | the situation worse. |
| Guidelines for pruning cuts are outlined in ANSI | | | | It is true that trimming trees is an essential part |
| z133 and the ISA at treesaregood.org and should | | | | of maintaining a property. However, the way in |
| be followed by anyone who does this work. | | | | which they are trimmed is critical to achieving |
| The next most common reason for pruning is the | | | | positive outcomes. We can do more harm than |
| removal of dead wood. Dead wood eventually | | | | good if we do not understand the science behind |
| falls from a tree if it is not cut out first, posing | | | | the practice. Consult an arborist and check his or |
| danger to anyone and anything below it. Worse | | | | her credentials so you can understand the best |
| yet, dead wood tends to fall from trees on calm | | | | practices as they pertain to your trees. |
| weather days rather than in storms, so the risk | | | | |