Environment Task Force Newsletter
Ohio State University Extension
Winter, 1998, v1 #4

Deicing Salts Can Cause Blood Pressure to Rise

Kyle Sharp, Associate Editor Communications and Technology

Homeowners who spread too much salt on driveways and walks this winter may be sowing seeds of stress and frustration. Rock salt and other deicers can damage nearby grass, shrubs and trees if not used properly, said an Ohio State University Extension landscape specialist.

Every winter, the Ohio Department of Transportation spreads an average of 360,000 to 390,000 tons of salt on the state's roads and highways in addition to what private owners use. When this salt is splashed onto evergreen foliage or shrubs by vehicles, people or the wind, it can cause browning, die-back or eventual stunting. In extreme cases, plants could die, Mary Ann Rose said.

Wind-driven salt spray can affect plants 100 to 150 feet from a highway, depending on the force and direction of the wind. Symptoms typically appear on the side of plants facing the salted area, but entire plants can be damaged if large amounts of salt are used and winds are harsher than normal.

Salt damage on evergreens begins to appear in late winter or early spring as needles turn progressively brown from tip to base. Damage to deciduous plants-those that shed leaves in the fall-will not be noticed until spring, when injury to new buds will be apparent, Rose said.

Chloride from airborne salt spray damages plants by accumulating to toxic levels in foliage and buds. Salt on stems and buds can dry up plants by drawing water from them.

Salt also can damage plants by collecting in the surrounding soil. High levels of salt in soil prevents plant roots from absorbing water and nutrients. In essence, roots experience a drought situation even though moisture may be available, Rose said.

"Salt in the soil is probably more serious than airborne salt. If rain doesn't move it out of the soil, new leaves and growth will come out damaged in the spring," she said. "It is more likely to kill a plant outright."

All salts and deicers can cause damage if not used properly. People using deicers should follow product label directions closely and apply what is recommended or less, Rose said.

Other tips to help prevent salt damage to plants are:

• Grade walks so they drain away from plantings.

• Homeowners could rinse plants sprayed by salt with water, but this may be difficult in the winter.

• Use sand, gravel, kitty litter or cinders instead of salt. These provide traction necessary for walking and driving without damaging trees and shrubs.

• Don't pile salty snow or slush near trees or shrubs or in places that drain onto them.

• Check your trees and shrubs early this spring for the symptoms of salt damage.

• If you suspect salt damage, have your soil tested for soluble salts. That test is not part of the standard soil mineral test offered by county Extension offices, but it is available for a small extra fee. Ask your county Extension office for more information.

• If you do have excess salt in your soil, flush areas near tree and plant roots with tap water as soon as weather permits.