Every winter brings its annual a-salt on roads and walkways. In icy conditions, salt may be necessary for safety, but too much of it is worse than a bad pun. Cars, equipment, and concrete suffer in obvious ways, but damage to trees and other woody plants is less visible. Salt injures trees and shrubs by several means.
When road-salt spray hits twigs, buds and, in the case of evergreens, foliage, such direct contact causes yellowing of needles, and subsequent death of evergreen twigs and limbs. It also leads to stunted or deformed growth, such as witches’ brooms, on hardwoods. Severe or repeated direct exposure, especially for sensitive species like white pine or cedar, can kill the whole tree. » Continue Reading.