What Type of De-icer Is Least Harmful to Your Ann Arbor, MI Yard?
After spending the spring, summer, and fall nurturing your yard, along comes winter with its ice and snow. Ice, snow, and slick sidewalks that requires de-icing to improve safety for the neighbors and visitors. Unfortunately, de-icers can negate all the nurturing of plants, grass, and shrubs.
Common De-icing Compounds
The most common de-icing compounds used in Ann Arbor Michigan are as follows:
- Rock salt –sodium chloride
- Calcium magnesium acetate
- Calcium chloride
- Magnesium chloride
A degree in chemistry is not needed to decide. Read the labels carefully, then read the following:
Sodium chloride – rock salt
Most people are familiar with this because it’s the most-used de-icer in the United States and Canada as well as in Ann Arbor Michigan. The run-off resulting when snow and ice melt, taking water into the roots of grasses and flowers can kill or stunt those same grasses and flowers. Shrubs and trees are particularly susceptible to the effects of spray or drift from roadways upon dormant stems and buds of woody plants and on the stems, buds, and needles of evergreen trees and shrubs.
Calcium magnesium acetate
This is biodegradable and has little effect upon plants because of its low toxicity. This compound is composed of dolomitic limestone and acetic acid (vinegar) and has a low effect upon plants and animals. It’s more expensive than other types of de-icers, roughly twenty times the cost of salt. This compound works down to 25 degrees Fahrenheit, but it is prone to becoming diluted and then refreezing.
This compound usually is dispensed as pellets and is sold in shaker containers. It’s less toxic than magnesium chloride and sodium chloride, but does have an effect upon plants and animal life. It heats as it melts and can work down to -25 degrees Fahrenheit, but it attracts humidity from the air that keeps the pavement wet and is corrosive to metal. Residue can be tracked inside and is harmful to carpets, tiles, and shoes. The compound costs three times the amount of salt.
High concentrations of this chemical will kill plants, although to reduce toxicity it’s often combined with byproducts from corn and grain that reduce the amount of magnesium chloride in the compound. Note that the byproducts reduce the efficacy of this compound in the de-icing process, so it is tempting to apply more for better effect. This compound works down to -13 Fahrenheit, but also collects humidity and is about twice as expensive as salt.
Most chemical compounds affect the stability of concrete. An excellent study on this was done by the Utah Department of Transportation (www.udot.utah.gov/main/uconowner.gf?n=8081525197623431), which can be downloaded and examined as a .pdf file.
Remember that the purpose of these compounds is not to eliminate ice – the purpose is to loosen the bond between ice and the sidewalk or whatever you want to free from ice so it can be easily scooped from the surface. Apply only as much compound as you really need to reduce possibilities of damage to growing plants and animals.