We’ve already had a few brushes with winter weather here in northeast Kansas, and there are chances of more ice and snow on the horizon. Because this is only the middle of December, there will most likely be (but it’s hoped not) many more instances this winter in which de-icers are necessary, so I thought this would be a good time to familiarize you with the common ice-melters on the market.
As far as de-icers go, we have many choices of products to use, but there are some differences between these products that can be important. None of these de-icers are quite ideal, as each one has its share of drawbacks, but it’s nice to know there are alternatives to a shovel. The five most commonly used de-icers are: calcium chloride, sodium chloride (rock salt), potassium chloride, urea and calcium magnesium acetate.
Calcium chloride is the traditional ice-melting product. Though it will melt ice to about minus 25 degrees Fahrenheit, it will form slippery, slimy surfaces on concrete and other hard surfaces. Plants are not likely to be harmed unless excessive amounts are used.
Rock salt is sodium chloride. It is the second most efficient material of these and is the least expensive material available. It is effective to approximately 12 degrees Fahrenheit but can damage soils, plants, and metals.
Potassium chloride is the third most effective material among those listed here. It is expensive, but works well as a de-icer when mixed 50/50 with rock salt. Potassium chloride can cause serious plant injury when washed or splashed on foliage. Both calcium chloride and potassium chloride can damage plant roots.
Urea (carbonyl diamide) is a fertilizer that is sometimes used to melt ice. Though it is only about 10 percent as corrosive as sodium chloride, it can contaminate ground and surface water with nitrates. Urea is effective to about 21 degrees F. Urea is simply nitrogen fertilizer — the same thing that is put on thousands of yards and gardens. As long as it is carefully used, it is about as environmentally friendly as fertilizing your yard or garden, and because it is a fertilizer, urea won’t harm surrounding plants if it is used at the recommended rates for ice removal.
Calcium magnesium acetate (CMA), a newer product, is made from dolomitic limestone and acetic acid (the principal compound of vinegar). CMA works differently than the other materials in that it does not form brine like salts do, but rather helps prevent snow particles from sticking to each other or the road surface. It has little effect on plant growth or concrete surfaces. Performance decreases below 20 degrees F.
Limited use of any of these products should cause little plant injury. Problems accumulate when they are used excessively and there is not adequate rainfall to wash or leach the material from the area. Because limited use is recommended, it is best to remove the ice and snow by hand when possible. When chemicals are applied, remember to practice moderation. We’re often prone to over applying just to make sure the ice and snow melts. Keep in mind this can damage concrete surfaces as well as the plants and grass growing along the walks and driveways. These problems normally do not show up until spring or summer.
Another option besides a chemical de-icer would be an abrasive substance to apply to icy walkways. Sand, sawdust, and other similar materials can help to provide some anti-skid properties to your problem area. These abrasives can also be mixed with a chemical de-icer (1 part de-icer to 3 parts abrasive is a good ratio) to provide a useful combination of materials to use in the battle against ice and snow.
If you have any questions about products or methods used for melting and removing ice, feel free to contact me at the Leavenworth County Extension Office at Hughes and Eisenhower roads in Leavenworth, call (913) 250-2300, or send an e-mail at firstname.lastname@example.org.