Salt can damage plants in two ways: through the air coming in contact with new buds or through the soil coming in contact with the root system. The chlorine and sodium (which the salt breaks down into) enter the tree and blocks essential nutrients from entering. Heavy salt in the soil can also inhibit the trees ability to take up water (as well as compacts soil and effects the PH) which can cause drought-stress.

Damage to look for : Conifers may having browning needles on branches facing the road Salt uptake from soil can cause needles to turn bluish Twig and leaf die back Small trees suffer more damage than large trees due to the root size