“Will snowbanks damage my trees or shrubs?” That’s a question that many homeowners in New Jersey find themselves asking – and it’s a good one to ask since the potential snow damage to trees and shrubs is a reality where we live.
Winterizing your trees and shrubs to prepare them for winter is always a good precaution to take. However, there are some situations in which no amount of winter preparation will protect your plants from extreme weather.
In this article, we’ll tell you everything you need to know about the impact that snowbanks (along with related issues like ice and road salt) have on trees and shrubs. You’ll also learn:
- the unexpected ways in which snowbanks can damage or kill plants,
- how to prevent snow damage to shrubs and trees,
- whether you should remove snow immediately to protect your shrubs, and
- the steps you should take if snowbanks do damage your plants.
Let’s get started!
Will Snow Damage My Trees or Shrubs?
Although winter weather isn’t always damaging to plants – especially if you’re diligent about only growing plants that are hardy to your growing zone – it has the potential to be dangerous.
Both heavy snow and ice storms can damage shrubs and trees, with snow becoming more harmful when it is piled up in a snowbank.
Large amounts of snow can cause tree limbs to snap. And the weight of compacted snow, whether from repeated snowfalls or snow shoveled into piles, can easily break branches and lead to stress.
But it’s not all wintertime doom and gloom! In fact, some snowfall is actually helpful when it comes to getting your trees and shrubs through the winter. A bit of snow cover can insulate plants from the wind and from sub-zero temperatures.
Plus, it’s important to note that some snow and rain (even freezing rain) can provide plants with the moisture they need to survive. Dry conditions in the winter make plants more likely to succumb to cold damage – especially evergreens.
Which Trees and Shrubs Are Affected Most by Snow Buildup?
Heavy snow can damage shrubs and trees, even when it’s not piled into snowbanks.
Deciduous trees tend to withstand the pressure of heavy snow and inclement weather conditions a bit better than evergreen ones. That’s because evergreens have dense crowns that have a tendency to collect snow, allowing it to accumulate until it snaps branches.
Deciduous trees have bare branches so, while ice can still pose a problem as it gathers on the limbs, the snow usually doesn’t build up as readily.
That said, all kinds of plants can be affected by heavy snow and ice buildup. For example, trees with two central leaders that come together in a V-shaped crotch often split down the middle, making them more likely to be damaged than trees with one central leader. You’ll often see this happen to Bradford pear trees.
Multi-stemmed evergreens like arborvitae and junipers, along with deciduous trees with weaker wood, like silver maple, are most likely to succumb to snow-related damage.
How Do Snowbanks Damage Trees and Shrubs?
Snowbanks form when snow is plowed off roads, driveways, and parking lots. They can also be created by shoveling or blowing snow into mounds. And snowdrifts form when windy weather blows snow into heaps.
In all of these situations, any shrubs or smaller trees that get buried beneath the snowbank (or surrounded by it) will be vulnerable to several types of snowbank-related damage.
Winter salt use has the potential to seriously damage trees and shrubs. In fact, the most common way that snowbanks injure shrubs and trees is via the buildup of road salt and other deicing chemicals.
Once the snow melts, the chemicals leach into the soil and can poison shrubs and trees. Salt in the soil will prevent plants from being able to take up water, slowly killing them from dehydration even if the soil has plenty of moisture.
Sand, Gravel & Anti-Slip Materials
Sand, gravel, and other anti-slip substances (such as kitty litter or chicken grit) tend to be less toxic to plants but can still harm trees and shrubs, especially if they were treated in any way.
When sand, gravel, or grit are mixed with snow, they increase the weight of snowbanks on the shrubs beneath, breaking branches and even snapping shrubs off at the base. When the snowbanks melt, you’ll be left with a heavy, gritty layer on top of the soil, making it more difficult to flush accumulated salt away. And if this layer is up against tree trunks, it can lead to fungal problems and decay.
Weight of Snow
Heavy amounts of snow piled against shrubs and trees can be damaging even if de-icing materials aren’t used. Snow is heavier than you might think, particularly as it starts to melt. Over the course of the winter, snowbanks often turn into large blocks of heavy ice as fluctuating temperatures cause the snowbanks to thaw and then re-freeze.
Eventually, this heavy ice can put too much weight on the branches, causing them to snap.
Ice is harmful to plants even in relatively small amounts, but when it’s piled heavily against a tree or shrub, it can be even more dangerous.
Like snow, ice is heavy. Repeated cycles of freezing and thawing (which are common here in New Jersey, especially in the late winter) can cause ice to form around branches. When snowbanks melt in spring, branches that are encapsulated in ice will be dragged downward until they break or tear off.
As the snowbanks begin to recede in the spring, you might assume that all of your weather-related plant issues are over.
However, a rapid melt can make it tough for the soil to respond appropriately. If the ground is already saturated with moisture, flooding can pose a problem for your shrubs and trees.
Flooded plants suffer from weakened root systems, root rot, and fungal diseases. These can stunt the growth or even kill a shrub or tree.
A final factor that many people don’t think about is animal damage. Under a deep snowpack, it’s easy for rodents and other small animals to get to the trunks, stems, and bark of plants – and turn them into a tasty snack.
Usually, mature trees and shrubs can recover, but those that were recently planted or in poor health may have a harder time bouncing back. And if the bark is eaten or torn off all the way around the trunk, the tree or shrub will likely die.
How to Prevent Snow Damage to Trees and Shrubs
There are a few ways to prevent shrubs and trees from being damaged by snowbanks.
Consider Where You Plow
Whether you plow or snow blow your own property, or you hire someone to do it, see if there are ways to redirect where the snow is piled.
Can you move the piles of snow so that they aren’t gathered around shrubs and trees? Can you prevent runoff problems by placing snowbanks downhill from your plants instead of uphill?
If you are growing foundation shrubs under eaves where snow can slide off, can you install A-shaped wooden frames to shelter your plants?
Spray an Anti-Dessicant
Using an anti-desiccant spray is a good idea, too. Also known as an anti-transpirant, it can help evergreens retain more moisture in their leaves so they don’t dry out and die over the winter.
A lesser-known benefit of anti-desiccant treatments is that it can help protect shrubs against salt spray from nearby roads. While road salt that leaches into the soil will still affect plants, an anti-transpirant can reduce the amount of salt that’s absorbed into the plant’s leaves.
Anti-desiccant treatments are especially helpful on some of our favorite landscaping shrubs here in New Jersey, such as holly, laurels, and rhododendrons. Apply this spray before temperatures dip below freezing.
Wrap Shrubs with Burlap
Consider wrapping your evergreen shrubs and smaller trees, like arborvitae, euonymus, or skip laurel, in burlap. Burlap protects tender young shrubs from the freeze/thaw cycle and snow or ice buildup, but it also helps keep road salt off the plants. Not only can it prevent the scorched look that arises from salt damage, but it can also keep salt off leaves.
Burlap strips or even twine can also be used to help upright shrubs like arborvitae or junipers to hold their shape under the weight of heavy snow.
Prune Trees and Shrubs
By reducing the overall size of a shrub or tree, thinning the crowns, and refining the branch structure, you can lower the likelihood that vulnerable branches will snap or die back over the winter.
The dormant season in winter is a great time to prune. But trees and shrubs can also be pruned before winter arrives if you’re concerned about snow, ice, or snowbank damage.
Add a Layer of Mulch
Mulch might not do anything to prevent the weight of snow and ice from harming your trees.
However, it helps moderate soil temperatures and may be able to slow the progress of chemicals and salt as they leach into the soil.
Plus, by adding organic mulch, along with a natural fertilizer like compost, you’ll be making sure that essential nutrients are available to the tree roots as soon as they thaw out in spring. This can help them bounce back and recover more quickly from any wintertime injuries they sustained.
Do a Preventive Tree Inspection
Finally, always take the time to have a preventive tree inspection done each year. This will help you identify any problems with your plants that need to be addressed in order to avoid winter damage.
A certified arborist will be able to see where shaping or removing a branch or limb might be needed or where removing dead or diseased branches can improve the overall health of a tree.
What to Do if Snow Damages Trees or Shrubs
Despite your best efforts, you may find that your plants are still damaged by the snow. Here are a few things you can do.
Carefully Remove Snow
When snow begins to build up on branches, you might worry that the weight will cause them to snap. Light amounts of snow don’t need to be removed from branches.
However, heavy snowfall should be removed from shrubs and small trees, ideally as the snow is still falling. If you wait until the storm is over, the snow might harden and ice over – removing it might do more harm to the plants than you intend to do.
If you’re worried about tree and shrub damage from snow, one of the best things you can do after the fact is to break up the snowbanks left from plowing if they are located around young trees and shrubs.
Shovel the snow elsewhere so that, as it melts, the runoff will flow away from the tree. This can reduce the likelihood of salt contamination, flooding, and snapped branches.
You can also consider where there might be a risk of snowbank runoff. If melt water is going to flow directly toward your plants, you can buy sandbags and lay them on the ground to direct the water away from your trees.
As the ground thaws, begin a weekly regimen of deep watering. This might seem counterintuitive – especially since the ground is already wet. However, most tree damage from snowbanks has to do more with chemicals than saturation. This process will help flush chemicals and salt from the soil.
Prune Damaged Branches
Again, pruning is one of the best steps to take if your shrubs are damaged.
On smaller trees, broken branches can be pruned all the way back to the main trunk. Most deciduous shrubs, along with evergreen shrubs such as cherry laurel and rhododendron, can also be pruned heavily in the spring to restore their structure and appearance. Some shrubs, such as forsythia, can be cut right to the ground and will grow right back.
Save Your Trees and Shrubs from Snowbank Damage by Hiring a Professional
Of course, one of the best ways to help your shrubs and trees recover from snowbank damage – and prevent extensive snow damage – is to hire a local arborist to help.
Alpine Tree’s team of tree service professionals can determine which of your plants can be saved – and will help you do it as quickly as possible. Sometimes, saving plants that were damaged by snow is as simple as quick pruning.
Contact Alpine Tree today for a free consultation!