P&PDL Picture of the Week for
February 9, 2009

Salt Spray

Mike Mickelbart, Assistant Professor, Horticulture & Landscape Architecture, Purdue University

De-icing salts are useful for melting snow and ice on roads and walkways, but they can do a lot of damage to plants. Salts can damage plants in one of two ways. Evergreen trees such as pines can be damaged when salts drift directly on to foliage. The salts can burn foliage or cause tip dieback. When salts accumulate in the soil, they can be taken up by plant roots and transported to leaves where they cause burn. This leaf burn typically occurs around the margins of the leaves. The damage is usually not seen until later in the growing season, so be aware of the potential damage this winter.

There are some things you can do to avoid or minimize any potential damage:

Avoid using salts — Try using sand to make walkways less slippery.

Keep plants healthy and water well in the spring — Healthy plants are more tolerant of many problems, including salt injury.

Provide adequate water in the spring — If you suspect salts have accumulated in an area, deep-watering the area will help to flush the salts from the soil.

Plant salt-tolerant plants near roads and salt-intolerant trees away from roads.

A list of salt tolerance of common Midwestern plants is available on the following publications (pdf files):

AS-458 The Use and Application of Salt in Aquaculture

HO-142 Roadside De-Icing Salts and Ornamental Plants

FNR-FAQ-10-W White Pine and Salt Tolerance

Click image to enlarge

Salt damage

Purdue Plant & Pest Diagnostic Lab Purdue Cooperative Extension Service