De-Icing Salt Harms Trees!

Sometimes, the solution to one problem creates a problem elsewhere. While road salt can keep us safe on the roads during icy weather, did you know that it can have detrimental effects on trees and landscape plants? Even worse, symptoms from this winter may not appear until late summer or even years later. Not only can salt damage foliage, it can stunt tree growth and in severe cases, can lead to death.

“Salt deposits migrate to the stems, buds and roots of trees,” explains Tchukki Andersen, BCMA, CTSP*, staff arborist with TCIA. “This causes disfigured foliage, stunted growth and severe decline in tree health. Salt runoff washes from pavement into the ground, increasing salt levels in the soil.”

Fir trees exhibiting road salt damage. Photo courtesy of Michigan State University Extension.

The Tree Care Industry Association offers the following suggestions to prevent tree damage:

• Avoid use of de-icing salt unless necessary. Mix salt with abrasives such as sand, cinders and ash.
• Use alternative de-icing salts such as calcium chloride and calcium magnesium acetate.
• Improve drainage of soils. Add organic matter such as activated charcoal or gypsum, and thoroughly leach salt residues from the soil.
• Erect barriers between pavement and plants.
• Plant trees in locations away from any type of salt spray.
• Plant salt-resistant trees in areas where high salt spray is inevitable, i.e. near walkways, driveways or roads.
• Provide adequate irrigation and mulching to reduce water loss.
• Prune properly and add fertilizers to correct nutrient deficiency as indicated in spring soil testing.
• Control tree damaging diseases and pest infestations.

Sources: De-Icing Salt Can Harm Landscape Plants: http://tcia.org/blog/business/de-icing-salt-can-harm-landscape-plants