Winter has hit many parts of the United States, and the frequent practice of ice melt abuse has surely followed. It is important to be cautious in the coming months to avoid serious damage to lawns and landscape beds.
At the first sight of slippery ice, and sometimes even before it forms, mostly for liability reasons, private businesses and municipalities start applying ice melt materials, usually a combination of salts, in great abundance to any surface someone can slip and fall on or slide a vehicle on. Nobody is usually going to complain about a dry surface after a big snow or ice storm, when attempting to get around for work, errands, or recreation, but come springtime, the residual effects can be quite a pain to deal with.
In addition to tracking it into vehicles, garages, homes, and businesses, often damaging concrete, tile, carpet, and other flooring materials, people don't always take into consideration the residual ice melt that vehicles pick up and discard from the roads onto driveways and sidewalks. Through the process of snow removal, whether by shovel, snow blower, or plow, people often move the snow into lawns and landscape beds in an attempt to keep the hard surface areas clear.
The removed snow will carry, in addition to oil and other chemicals from the roads, a greater deal of salts into the sensitive landscaped areas reducing sustainability. Much like in animals, overdoing the salt intake in soils, roots and foliage can be deadly to the landscaped environment.
The primary salts that make up ice melt products are usually one or more of four major types of chlorides; sodium, potassium, calcium, and magnesium.
Sodium chloride, which is what table salt is usually made out of, is the cheapest, but most deadly to plant material.
When in water, the sodium and chloride ions separate and do significant damage to plants. The sodium replaces valuable nutrients, while the chloride gets into the foliage, causing a disruption in photosynthesis.
The fact that sodium chloride is cheap means that it is widely used, especially in the current cost-conscious economy. The fact that it does dual damage means that property owners need to be extra cautious about where they place their snow when shoveling the drives and walks.
Not all commercially-used de-icer salts that make it onto private property are sodium chloride, but while the magnesium, potassium, and calcium products may be less harmful, they are still dangerous in high concentrations, especially in heavy snow years.
When using de-icers at home, people should remember two things.
First, if the de-icer is being used strictly for traction, it is better to use coarse sand. Even though it may require clean-up, this is much cheaper and easier than replacing plant material.
Second, if salt is absolutely necessary, calcium chloride works best at lowest temperatures, while potassium chloride is only effective to 12 degrees fahrenheit, no less. Magnesium chloride and calcium magnesium acetate fall somewhere in the low single digit temperatures as an effective product. It's best to try to avoid sodium chloride altogether.
As for snow removal, it's not that someone needs to find a special place for all driveway and sidewalk snow, but it's important to be aware during removal, so a big chunk of road salt doesn't end up killing off landscape, lawn and garden plants.