Effect of deicing salts on woody vegetation along Minnesota roads: final report

Information was collected on amounts of deicing salts used and methods of application. Planting practices and investment were also surveyed. Techniques are presented for the recognition of soil-salt and spray-salt damage using visual symptoms and chemical analysis of leaves and soils. Proof was obtained that salt causes much of the twig dieback in hardwoods and needle browning in pines observed along certain Minnesota roadways. The locations are defined where salt-spray and soil-salt damage are likely to be high, moderate, or low. Species are rated for their sensitivity to soil-salts and winter spray-salts. A brief history of salt damage in Minnesota is presented, and the seriousness of current damage is evaluated in terms of mortality, reduced growth and disfigurement, and increased maintenance costs. Seven ways to reduce salt damage are presented including a planting guide to match species to site. Future prospects are estimated for salt damage in Minnesota. A permanent plot system is described that will monitor build up in plant and soil sodium and chloride as well as changes in the vegetation caused by salt damage.