TO PRUNE OR TO CABLE
When urban foresters visit a property, they’re not sure of what they will find because there is no shortage of diseases or insect problems. These problems are known to plague home landscapes as well, so when the structural integrity of trees is threatened, either of the following courses of action should be employed.
Cabling
Subordination pruning
Subordination pruning
Most clients will inquire as to what they should do to reduce the chances of tree damage where high winds and storms are concerned. Some trees such as oak, linden, maple and ash are mostly concerning due to their propensity to develop co dominant leads. This occurs whenever two vertical leads grow at a certain point of attachment. When this occurs, a weak point is created in the tree structure due to the following;
Included bark
Weight load of the limbs
Pressure put on the attachment point
Trees whose co-dominant leads mature usually experience an increase in splitting caused by storm damages. Other major contributing factors for tree damage in the urban environment include ice, wind and heavy snow loads but with proper pruning techniques, repair is possible after damage caused by the storm. In most cases, trees are usually damaged beyond repair and what happens then is that the tree needs to be removed and the stump ground. Where pruning trees is concerned, we as urban foresters are tasked with being proactive when the trees are young for the purposes of helping in the proper development of their structure. Extensive research has been done by Dr. Edward Gilman, who is a professor at the University of Florida, in regards to the reasons for subordination pruning. Having said that, arborists can now use his tutorials as a guide in what subordination pruning entails.
Great results have been obtained from structural pruning and the benefits gotten from it should not be ignored by city foresters who have been given the responsibility of caring for trees in the public domain. Most communities barely do anything to care for trees and the majority leave that task to Mother Nature. Others do the bare minimum which includes removing deadwood and raising low limbs. What has time and again been proven are the benefits of subordination pruning to communities who use the techniques laid out.
Subordination pruning has garnered great results when it’s performed on young trees, however, in cases of mature ones, it is best to do cabling.
Cabling and Bracing
Matt Evans, who is a board certified master arborist, has for the past ten years developed the cabling program for Ryan Lawn and Tree urban forestry department. This is a lawn and tree company that is based in Overland Park, Kansas and has four other branches across Missouri, Oklahoma and Kansas.
Following the standards set by ISA and ANSI, company arborists now install cables in trees that have co-dominant leads for the purposes of adding supplemental support. This helps in enabling the cable leads to move as one unit as opposed to oscillating, in the event that there are heavy winds. The upper part of the canopy is usually offered extra support for the purposes of successfully shouldering extra weight from additional weight loads of ice and snow.
We as arborists recognize the fact that nothing is ever guaranteed because we deal with organic material where cabling is concerned. Recognizing that the tree has a structural defect and cabling it is what we do, but this does not mean that the problem is fixed. It simply means that supplemental or additional support has been offered to the tree.
Call on us today and you will be glad that you did!
