Foliar Damage, Ion Content, and Mortality Rate of Five Common Roadside Tree Species Treated with Soil Applications of Magnesium Chloride

摘要: Sensitivity to magnesium chloride (MgCl2) was assessed on five common roadside tree species by maintaining soil concentrations at 0-, 400-, 800-, or 1,600-ppm via MgCl2 solution over four growing seasons. Evaluations of growth, leaf retention, foliar damage, and ion were conducted. Water potentials measured two species. Foliar positively correlated with damage in all Conifers exhibited mild during the first season but moderate severe winter second season. The highest treatments caused loss, mortality Douglas-fir, lodgepole, ponderosa pines after seasons limber pine Aspen also displayed crown loss abscised damaged leaves flushed asymptomatic throughout treatment aspen 4 years. Approximately 13,000–17,000-ppm associated conifers ranged from 13,000- 33,000-ppm fully necrotic leaves. foliage contained (24,000–36,000-ppm), had lowest (<14,200-ppm). Although reductions water potential, did not appear be under substantial moisture stress continued take up ions. Mortality 2 4 years can occur due high concentrations, transportation officials should consider these implications their management plans.