Easy-to-apply chemical fertilizers are often touted as the perfect de-icer. However they, too, can cause damage:
- Potassium chloride: Often sold as potash or Sylvite, this fertilizer is still salt. Lethal to pets, it's the most damaging due to the large amounts needed for any application to be effective. Works to -4°C/-28°F.
- Urea: While it doesn't corrode metal, this synthetic fertilizer promotes algae bloom, often creating high levels of nitrogen, ammonia and phosphorus in soil. It's five time more expensive than rock salt and only works to -5 °C/-23°F.
Green, but expensive
The newest de-icers considered 'super-green' are effective, but they can be pricey:
- Calcium Magnesium Acetate (CMA): This combination of dolomitic limestone and acetic acid (vinegar) is 100 per cent biodegradable, non-corrosive with little impact on plants and animals. Unfortunately it's 20 times more expensive than rock salt and only work to -3° C/25° F.
- Potassium Acetate (KC2H3O2):Non-corrosive for plants, animals and metals, this de-icer is still being researched. Eight times more expensive than salt and difficult to find, it does have the lowest working temperatures at -59° C/-75°F.
Bitter cold solutions
All de-icers are limited by their ice melt minimum effective temperature (MET) and in the bitter cold, natural ingredients are still the best solution. Sand is an excellent option because it increases traction and is non-toxic. Just be careful to clean up any excess in the spring so it doesn't clog drains and sewers.
Berezan offers a novel solution: "My favourite alternative to using salt on ice is bird seed. It has the texture to work well as a gripping surface and provides a welcome winter food source for birds. I buy the cheapest and largest bulk bag of bird seed I can find and use it all winter. Most bird seed is made up of annual grains so you get the added bonus of some interesting grasses sprouting up in the spring."
Beware of the "pet-friendly" label
"Pet-friendly" de-icers on the market are often made with ethylene or propylene glycol. They are toxic to most aquatic life, including fish and plants so they should be avoided unless you can ensure the run-off won't end up in storm sewers.
The best solution to ice removal
De-icers aside, the safest solution is still to remove snow and ice immediately. The less there is, the less de-icer you'll need.