Monday and Tuesday, a major winter storm dropped more than a foot of snow on parts of Nebraska and Iowa. The white stuff disrupted traffic and closed some schools—while blanketing other parts of the middle of the country. As winter continues in full force, out come the salt trucks and spreaders. But how will the plants fare come spring?
Each winter, people and trucks spread salt on sidewalks and roadways. Salt eliminates ice and snow by lowering the freezing point of water. By getting rid of ice hazards, people can walk and drive without slip-sliding.
Although salt helps get rid of one problem, it creates another: The melting ice creates salty water runoff.
Salt draws water from living cells—including plant cells. It also removes moisture from soil so that dirt becomes dusty clumps: not a nice place for plants to grow.
Damage from winter salt doesn’t usually show itself until spring or later. Then, new leaves can emerge pale green or yellow. Later in the season, leaves may appear scorched or turn their autumn colors early. Stems can also die back or be stunted. Older, well-established plants can sometimes recover from salt injury, especially if spring and summer rains are abundant.
Using less salt can help limit the salt problem. Highway studies show that de-icing salt is effective in smaller amounts if sprayed as a brine rather than spread as crystals.
Home gardeners can get rid of much of the salt by flushing the soil beneath a prized tree or shrub in spring with extra water.
Other salts may also be a promising alternative. Calcium chloride is less damaging to plants and soils than sodium chloride. It also melts ice faster and works at temperatures below zero degrees Fahrenheit. But it does still put the chloride ion, which plants don’t like, into the soil. It’s also more expensive and more damaging to vehicles than sodium chloride.
Another de-icing method is to spread something other than salt on the ice; gritty materials such as sawdust, unused kitty litter, wood ash, or sand have some effect by adding friction to slippery surfaces. Still, nothing’s perfect. These materials track indoors unless you take or shake off your shoes at your door.
Home gardeners could choose plants that tolerate salt when planting near the road, driveway, or walkway. Besides plants God designed as native to seashores, other salt-tolerant trees and shrubs include silver maple, horse chestnut, honey and black locusts, poplar, junipers, lilac, and Colorado blue spruce.
In the meantime, some areas of the country are enjoying what the National Weather Service is calling a “historic snow.” Stay safe out there!
(An icy plant in New Paltz, New York. Lee Reich via AP)
