While there are loads of crazy things happening in the world right now, one thing that we Minnesotans can be grateful for is our current weather situation. The early October snows had me and many others wondering if we were going to have one of “those” winters. The longer we go without snow and pretty tame temperatures, I think it helps to shorten up the winter considerably.
Since we don’t have to deal with the snowy conditions, yet, Murphy’s law says eventually we will have some sort of precipitation, and with that comes the need to use deicing salts on our driveways and sidewalks. While the need to keep from slipping and falling is just something that we think about during the winter months, deicing salts are also hard on our environment.
It is important to understand how deicing salts work in the first place. They reduce the melting point of water, which keeps ice from forming. Sodium chloride is the main deicer material that is used for homeowners. There has been a lot of research that has been done to find materials that are easier on the environment (and our cars) as well.
So why it is important to learn how much deicing salt to place on our driveways and sidewalks? The first important thing to remember is that as the snow melts and the ice melts it runs off. One small teaspoon of deicing salt can pollute 5 gallons of water, which equal our groundwater becoming polluted. Groundwater is what we use for drinking water in many communities. High amounts of deicer in our lakes and rivers also affect the oxygen levels of the water where animals live such as fish, turtles, and other amphibians.
There is more damage deicing salts can cause as well. This damage can include damage to concrete and natural stone. It also includes damage to our plants. If you have plants that are in the boulevard on your street, these gardens are in particular danger from accumulating salt from our efforts to keep streets cleared during the winter months.
Signs of salt damage on plants include plant death, brown needles, and leaves plus loss of foliage. Julie Weisenhorn, Extension educator with the U of M, has an excellent handout or online information which can be found at https://extension.umn.edu/lawns-and-landscapes/effects-deicing-salts-landscapes
The best way to tackle deicing salt from becoming a problem in your yard is to tackle the ice and snow first with a shovel if you can do so. Let the sun work for you and allow it to melt as much snow and ice as possible. Remember that more is not better! According to Weisenhorn, “a coffee mug is all that is needed for a 20-foot driveway or roughly 10 sidewalk squares.”
If you have a garden that is near a place in your yard or along a boulevard that will see a lot of salt problems in the winter, then you can also choose salt-tolerant plants including grass seed or sod. Planting evergreens close to these areas should be avoided at all costs or at the very least, where possible, plant trees, shrubs, and other perennials at least 7 feet away from where salt could land during plowing efforts.