Levels of deicing salt producing injury on apple trees

A suppression of flowering and dieback of terminal shoots in apple (Malus sylvestris Mill.) trees was associated with increased levels of Na and Cl in the twigs. These symptoms were observed on both roadside trees exposed to salt spray, and trees sprayed experimentally with 2% aqueous solutions of road salt. Concentrations of Na and Cl exceeding 0.20 and 0.50%, respectively, of the dry weight were associated with injury to the trees.