Be careful of plants as you de-ice sidewalks

RBC I Winter has unofficially arrived with minus-41 degrees Fahrenheit reported on Piceance Creek. So get ready for snow and ice for the next few months.
With that in mind, I would like to talk about the differences in de-icing products, which are primarily comprised of salt. Salts can cause injury to trees, lawns and shrubs, they can corrode concrete and even do bodily harm to humans if handled improperly. The most problematic element in these salts is chloride. It is a corrosive ion that damages metal and concrete and is toxic to plants.
While most plants have some tolerance to salt injury, repeated applications of de-icing products during the winter can result in dieback or even death the following spring.
Misapplications of de-icers (i.e. dumping piles or using too much) can wash into the storm sewers, causing pollution. Before buying or using any product, read the label carefully and thoroughly and use only as directed. A few of the salt products you might run into while shopping include:
Sodium chloride: It is the most widely available and the cheapest. It doesn’t cause corrosion to concrete, and melts ice best when temperatures are in the 20s. It is the most damaging to plant material. If you use this product, use sparingly and in small amounts.
Potassium chloride: It is expensive and not as widely used as a de-icer because of rising costs of fertilizer. It works best when temperatures are above 15 degrees Fahrenheit. Because it is most commonly used as a fertilizer, it’s relatively safe to apply near plants.
Magnesium chloride: It’s the most common product used on our roadways before storms (applied as a “brine”), because it lowers the freezing point of soon-to-arrive precipitation. It can melt ice down to minus-15 degrees, which is a nice benefit. If applied in moderate amounts, it’s relatively safe for plants and pets. Its corrosion potential is low, as are its pollutant possibilities.
Calcium magnesium acetate (CMA): A new de-icing product, it has low corrosion potential, so it’s less damaging to cars, metals, sidewalks and plants. It is also biodegradable. Its ice-melting properties are equivalent to traditional de-icers, but the cost will make you gasp. It may be 20 to 30 times as expensive as sodium chloride products.
These are often touted as “pet friendly.”
Before using any product, clear away as much snow and ice as possible. Get out your shovel and do your best. Remember, de-icing products are not meant to melt all snow and ice, but aid you in your removal efforts.
If you want to avoid chemistry in your landscape, then consider using sand or kitty litter. While they don’t melt snow, they can provide some much needed traction in slippery spots. Sand and kitty litter are also safe for pets and plants and can be swept up when the snow melts.
If you do use de-icing products near areas of vegetation, then use caution with potential salt build-up. If it’s an especially snowy year, you may consider leaching the areas next spring with clean water.
Try not to scoop snow laced with de-icing products directly on top of plants, especially if they are sensitive.
So enjoy the snow and the cold – and the hot beverage waiting for you when you get inside.

By Bill Ekstrom
RBC Extension Agent