Winter
injury is common on broad-leaved evergreens such as rhododendrons,
laurels, hollies, pines, spruces and firs. Symptoms include browning
on the outer leaf margin, brown needles, and brittle twigs.
Evergreen
plants are constantly transpiring (losing moisture through the stomates
in the leaf) throughout the year. In winter it is hard for a plant
to replace moisture loss since the water in the ground is frozen.
As a result tissue damage occurs. This condition is made worse when
winds and sunny days increase the moisture loss.
Ornamentals can be
prepared for this by watering late into the fall and applying anti-desiccant
treatments to the foliage.