Why is storm-proofing your trees important?
Trees bring enormous advantages to the value of a property, to the natural environment and to our quality of life. They offer shade and wind protection, and enhance the aesthetic value of our surroundings. During a storm, the natural beauty and financial value of your trees, and your property, can be lost quickly.
Natural perils include cyclonic winds, torrential rain, flooding, lightening and damaging hail. During a storm, some trees may be damaged partially and can be treated to recover, whilst others may be critically weakened. Under typical storm conditions, trees can withstand winds and lightning. They grow to cope with the normal external loading that comes with storm conditions. But cyclonic winds and flooding can destroy entire gardens. The intensity and duration of a storm is what determines minimal damage or widespread havoc.
Damaged trees pose risks to personal safety and property, and as such are concerning not only to property owners, but also to neighbours and the wider community.
So it’s critical to make the right decisions during and directly after a storm has passed through your property. An experienced arborist can help you decide if a tree will recover with treatment, or if removal is required.
One of the best ways to storm-proof your trees is to have a trained arborist conduct a storm risk assessment in the lead up to storm season.
Research into storm-damage provides important knowledge on why and how trees can fall when they are hit by a storm. This article offers information to homeowners to grow more storm-resistant gardens that minimize the effects of each passing storm season.
Common tree damage sustained in a storm.
Stem Failure: Cyclonic winds impact the weakest points within a tree. Trees can crack or snap at these points and large parts of the tree can fall. Weakened points may have been caused by previous injuries or if the tree was affected by disease or an infestation of insects. When a stem fails, repair is rarely possible. An arborist is trained to assess a tree, remove weakened parts of the tree and offer advice to eliminate hazards.
Branch Failure: Compromised branches are vulnerable in turbulent winds or lightning storms. When loaded with external forces, branches can snap or break. Branch damage will not typically kill the tree unless 50% or more of the crown has been impacted. These branches however are hazardous and pose serious safety ricks. Homeowners need to recognise tree damage and have hanging limbs or branches removed to reduce risks to surrounding trees and property. A certified arborist can assist as often compromised branches are difficult to identify and an expert inspection is required.
Crown Twisting: Poor pruning procedures can lead to uneven crowns. During strong winds, the branches within an uneven crown can be twisted. This can lead to the tree cracking close to any areas of weakness. This often results in significant damage to the entire structure of the tree.
A catastrophic result of a strong storm is the complete uprooting of a tree. Uprooting occurs when wind high in the tree pull on the trunk and the root system. A tree that is vulnerable by pest infestations or decay may be poorly anchorage in the ground, and may be easily toppled in strong winds. Tree roots can sustain significant stress during a storm and this can cause a tree to lean and to fall. A professional arborist can identify tree root weakness and advise on treatment or removal options.
What are the mitigation methods?
Research shows that trees that grow individually are impacted more by storms than trees that are growing in groups. Studies define a group as six or more trees spaced 2 to 3 metres apart, in an irregular spacing, not in rows. When planting trees, it is best to space trees to enable sufficient room for a robust root system. It is recommend to plant trees in quantities of five or more in well-spaced groups.
There are some tree species that resist cyclonic winds better than others. If you live in a storm-prone region, choose trees with a wind resistance factor. This refers to a trees ability to withstand cyclonic winds without breaking or uprooting easily. It is also recommended to planting different species of trees and allow trees of different ages to grow together. This diversity ensures your landscape copes best in bad weather.
Compromised, low wind resistance or old trees should be inspected in a pre-storm assessment. These trees are risky to people, property and to surrounding trees and garden. A certified arborist can give you expert advice to ensure your home or business is ready to weather the next storm season.
I'm currently studying a Masters in Environmental Science, because I'm passionate about trees and native wildlife.