As storm signals are raised and the wind starts to howl outside, everyone fears the wind may be too strong and cause a tree to fall. Now, that’s what this guide will help you prevent.
In this article, we’ll look at what type of trees are most likely to fall in the wind, the factors that make them vulnerable to windfall and how to prevent them from falling. So, keep reading to learn how to keep your property safe from tree windfall.
What trees are most likely to fall in the wind?
Trees most likely to fall in the wind are those with damaged roots, uneven canopies, two trunks and decayed wood, and tall trees.
Let’s discuss what makes each of these trees susceptible to windfall.
1. Trees with Damaged Roots
Every tree’s roots are essential in their strength and stability. Tree roots usually grow twice the radius of their canopy, and their large and absorbing roots should work to create a strong anchor that can withstand strong winds.
Conversely, when a tree has shallow roots, it cannot support the trees well as they grow, and it significantly increases its risk of getting uprooted, even by strong winds.
When a tree is planted in hard and compacted soil or poorly watered, its roots also have difficulty penetrating the ground and developing its roots. This also leads to shallow root development and weak tree anchoring, making it more vulnerable during strong winds.
Damaged roots can also weaken the tree’s stability, usually due to construction stress, rotting, pests and diseases. For instance, construction work around trees damages and restricts the development of a root structure, making them more likely to lean and fall during a storm.
2. Trees with Uneven Canopies
Trees need regular pruning to maintain their even canopies. Otherwise, an uneven tree canopy and crown growth will lead to a phenomenon called “crown twisting” and cause it to topple during high winds.
The strong winds usually exert force on these uneven canopies and cause torsional stress on the tree’s stems and branches, leading to cracking, splitting and falling. Crown twisting is also harmful to the tree’s old wounds and can hasten its destruction.
So, we recommend you consult an arborist to spot some cracks early on and teach you how to prune your canopies evenly and prevent this disaster.
3. Tall Trees
One downside to having tall trees is their vulnerability to a problem called “windthrow.” This refers to the tree uprooting by strong winds, usually because of shallow roots, weak wood, lack of pruning or heavy rain.
When strong winds hit the upper and lower trunk, the tall trunk and its leaves combine into a lever system, which uproots the entire tree from the ground. Some trees susceptible to windthrow are coniferous trees like pine, cedar and white spruce trees.
4. Trees with Two Trunks
Trees with codominant stems or two trunks are most likely to fall in the wind because they are structurally weaker since they grow from the same point at the base of the tree.
This setup also forces both trunks to compete for water, nutrients and other resources, leading to a weaker tree.
So, taking their uneven weight distribution and weak structural support and exposing them to strong winds, they’re more likely to break apart or be uprooted.
5. Trees with Decayed Wood
Trees with decayed wood are also most likely to fall during high winds because they are weaker, heavier and more brittle, making it easy to break and uproot them under stress.
Trees usually decay or get wounded due to lawn mower damage, improper pruning, vandalism and decay-causing fungi. These factors weaken the tree’s structural stability and increase its likelihood of falling when exposed to strong winds.
When over 40% of the tree’s trunk is decayed, it’s more likely to fall in the wind. Some signs of decayed wood that you should watch out for are hollow holes, large cracks, discoloration, bulges and growth of mushrooms.
What type of trees are most likely to fall during strong winds?
Evergreen trees and those with injured trunks are prone to fall during strong winds.
Evergreen trees have large canopies and leaves all year round. The leaves act like sails and catch the wind, making them more likely to topple.
On the other hand, trees with injured trunks are also vulnerable to wind because they have weaker support systems that make them more likely to break and less likely to withstand the forces of the wind.
Which tree species are prone to falling?
Tree species that are more likely to fall due to strong winds are the White spruce, Cedar, Bradford pear, Balsam fir, Willow Oaks, Water Oaks, Chinese elm, Norway maple, hemlock and Leyland cypress trees.
These species are more likely to fall because of shallow roots, weak wood, tall and slender build and lack of pruning.
Does tree location affect its likelihood of falling?
Location affects the likelihood of trees to fall. For instance, trees on coasts, hilltops or areas prone to strong winds are more likely to fall than trees in forests or sheltered areas.
When trees are in a forest, the wind force is shielded and distributed on other trees. As a result, it minimizes the stress a tree receives and its likelihood of falling.
On the other hand, wind blowing through trees in open fields will receive larger forces, making them more likely to fall. Those trees grown on loose soil, rainy areas, mountain slopes or suffering from deforestation are also at high risk of falling in the wind.
Other factors that can affect the likelihood of a tree falling are wind exposure, soil type, slope location and waterlogging can also affect the likelihood of a tree falling.
How much wind can a tree withstand?
Generally, a healthy tree can withstand wind speeds between 50 to 90 miles per hour. However, weak or damaged trees are more susceptible to wind damage at lower rates.
Other factors affecting how much wind a tree can handle are species, age, health and soil conditions.
For instance, oak trees are more wind-resistant than pine trees, while trees planted in well-drained soil are more likely to survive winds than those in poorly-drained soil.
Younger trees are also less wind-resistant than older ones because of their less developed root system and trunks.
Can you determine which way a tree is going to fall?
You can determine how a tree will fall based on the wind direction, lean of the tree and weight distribution.
Generally, a tree will fall opposite the wind direction. For instance, the tree is likelier to fall on the west if the wind blows from the west.
On the other hand, if the tree is leaning on one side, it will more likely fall in that direction. The same thing applies to weight distribution, as the tree will more likely fall in the direction where its heaviest weight is concentrated.
How to Protect Trees from the Wind
Now that we’ve tackled all the factors that make trees fall, it’s time to prevent these safety hazards from happening. Here are our tips on how to protect trees from the wind.
1. Keep the roots healthy.
Roots keep trees stable. If you’re staking young trees, allow them to sway to help stimulate root growth and trunk taper to stabilize the tree.
Here’s a table of the recommended open soil area around the trunk for the healthy development of roots.
Tree Size at Maturity | Minimum Open Soil Area around the Trunk |
Small (under 40 feet) | 10 by 10 feet |
Medium (under 50 feet) | 20 by 20 feet |
Large (over 50 feet) | 30 by 30 feet |
Planting trees in well-drained soil is also vital in keeping the roots healthy. This prevents them from rotting and weakening the roots, stems, trunks, branches and leaves of the tree.
You should also avoid compacting the soil because this can restrict the movement of air and water to the roots, which can lead to damage, pest infestation and diseases.
2. Systematic Pruning
Systematic pruning involves the regular removal of dead, diseased and damaged branches of trees in an orderly manner.
You can also thin the canopy of a tree to reduce its weight and make it more wind-resistant. With fewer branches rubbing against each other, the branches are also less likely to break off during strong winds.
We recommend that you prune during early spring or late fall to minimize stress on the tree and prevent attracting pests and diseases. Make sure to prune back to a healthy collar, where the branch meets the trunk.
3. Grouping
Trees that are alone or isolated are more likely to fall during storm winds, so it’s better to plant them in groups. In gardening, a group is defined as five or more trees sharing the same small space.
By grouping, the trees give mutual protection to one another as they help keep their roots stable and reduce the wind velocity each tree will receive. It will not only make trees resistant to storm devastation but also to attacks by pests and diseases.
4. Species Diversity
Planting a variety of species helps create a balanced ecosystem and reduces the risk of trees falling due to the strong wind.
The National Arboretum recommends that there should be no more than 10% of any one species, 20% in the same genus, and no more than 30% belonging to one family in every ecosystem.
It’s better if you choose native species so they can quickly adapt to the local climate conditions, develop strong roots and become more wind-resistant.
You can also plant diverse species in staggered rows, creating a windbreak that can reduce the force of the wind and protect the trees from damage.
Some trees you should avoid planting because they’re susceptible to wind damage include the Lombardy poplar, white pine, willow, cottonwood and aspen trees.
FAQs on Trees Most Likely To Fall in Wind:
Tall and large trees are most likely to fall. Since they have a higher center of gravity, they require more strength from the trunk to support their canopy, which makes it easier for strong winds to topple them over.
Winds weaken trees by causing them to lose their leaves, bark and branches. Without them, the tree is more susceptible to pests and diseases, making it more likely to fall over when exposed to strong winds.
The best wind-resistant trees are oak, maple and pine trees because they have deep roots and strong trunks that can withstand high winds.
Trees can fall over without wind because of pest infestation, diseases, damaged tissues or poor soil.
Winds can cause the tree to sway back and forth and exert force to stress its roots and trunk, eventually leading them to fall over.
A tree is more likely to fall due to strong winds, young age, diseases, pests and poor planting location.