In January, Midwest lawns and landscapes suffer from a variety of influences – cold, wind, misschevious children who beat on small trees and shrubs, cars that slide on the ice and into trees/shrubs in the front lawn…and speaking of ice, sometimes ice can be a problem too. Ice can be a problem on the lawn if it builds up and cuts off oxygen throughout the winter. During winter thaws, it can be helpful to break it up with a sledgehammer – not completely, not pulverized, just enough to create some cracks to allow air to penetrate.
The other damaging influence of ice is on our driveways, sidewalks and steps..not so much the ice, but the ice melt products that we use to get rid of it so that we can walk safely without slipping and breaking an elbow, hip or knee. These products can be quite caustic to the concrete, and if used excessively over time, will cause spalling and cracking, losing integrity of the surface. Adjacent plants such as trees, shrubs, perennials and turfgrases can be injured as well, killing shoots and roots.
Some of the influence is in the types of ice melt product used, and the other is in the amount used.
Prevention of damage to plants from these materials is not easy as sodium chloride, the best (and cheapest) product to remove ice is caustic to cement and damaging to tree and shrub roots as well. Less caustic options such as calcium magnesium acetate are less damaging but more expensive. Another option is to use less ice melt product and mix sand with driveway salt for traction. Of course, then the undesirable result is the need to sweep up the sand or deal with the mess, as well as the possible negative effects of mixing sand with clay soils where tree roots are growing. Sand and clay mixtures are not desirable for root growth as they provide less capacity for oxygen exchange, water penetration and root expansion.
Another consideration in the quandary of gaining the benefits of ice melters but minimizing their negative effects is what happens after the product is applied. In most cases, the products melt the ice and frozen snow, and a salty residue is washed or blown off the surface. In others, the modified materials are scooped up and thrown into the landscape to get them off the sidewalk or driveway. If this occurs over and over again, damage can occur akin to applying them directly as if they were fertilizer or a pest control product. To reduce injury, toss salty snow in various places, not always the same place. Spreading out the melted slush will diffuse the material over a greater surface area, with less being deposited in one small space. Of course, if it snows often, say over 15 times or so, then the minimization attempt my not achieve positive results…but you might feel better for having tried. Overall, a few wintry mix events are not troublesome for the landscape, but a multitude of occurrences should be managed with forethought in mind.