Proper tree pruning practices are important when attempting to limit storm and wind damage. During monsoon rains, the wet ground makes trees more susceptible to failure due to what we call the “sail effect”. The sail effect happens when trees have been primarily lifted – meaning the tree foliage has been trimmed for clearance. While removing low hanging branches for clearance is an important aspect of tree care, performing it alone leaves the majority of the tree’s weight in the top half – making it more susceptible to wind damage because the wind can’t move through the canopy. The key pruning practice in preparing your trees to for monsoons is crown thinning. Reducing the thickness of the canopy, while also pruning for needed clearance, allows wind to move through the canopy, reducing the amount of force strictly pushing against the canopy.
DLC follows and recommends the standards adopted by the International Society of Arboriculture (ISA) as outlined in American National Standards Institute (ANSI) A300-2001 Pruning and ANSI Z133.1-2000 when pruning trees:
- Crown Cleaning (removal of lower branches to provide clearance for view and/or traffic)
- Crown Thinning (selective removal of branches to reduce weight and increase air and light penetration not to exceed 20% of the total volume of canopy)
- Crown Reduction (removal of leader or lateral branches using proper heading cuts to reduce size, i.e. reduce leader or lateral to a branch that is at least 1/3 diameter of the branch being removed)
- Crown Restoration (removal of improperly pruned branches to restore more natural shape)
Even when following the above specification, it is recommended that you not remove more than 20% of the tree’s canopy at a time. Having an ISA Certified Arborist plan your work and and ISA Certified Tree Worker on the ground doing the work helps promote educated and experienced decisions when pruning your trees. Investing in proper tree pruning can save your Community time, money and nuisance when recovering from monsoon damage.
To experience the value of tree pruning by an ISA Certified Tree Worker, or to have an Arborist assess your tree inventory, contact Rebecca Herro.