Evergreens & Droop
An evergreen with drooping branches weighted down by snow forms one of the iconic images of northern winters. As trees age, the branches of many species naturally begin to droop, drawn down by the weight of their foliage over time. If you notice your evergreens beginning to look wilted, that may suggest a possible problem.
Several types of evergreen trees droop normally or begin to droop with age. The Norway spruce droops as it grows older, but its shape helps it to withstand heavy snowfalls without branch breakage, according to Colorado State University Extension. The Japanese evergreen oak and Canada hemlock also tend to droop.
Rhododendrons are popular shrubs that tend to be evergreen. Like evergreen trees, they also exhibit normal drooping foliage, primarily during the winter on very cold days. According to University of Missouri Extension, as temperatures drop, rhododendron leaves droop and curl. This normal behavior, which helps plants conserve water when underground stores are frozen and unavailable, requires no special attention or alarm on your part.
Some evergreens are prone to drooping because of the weight of excessive snow and ice on their branches, which can damage the trees. Species like arborvitae are particularly susceptible, but you can minimize droop and damage by taking precautions in the fall, or when snow is forecast. Wrap rope, twine or pantyhose around the tree to keep the branches together, advises Iowa State University Extension. When snow falls, carefully brush it off with a broom, but don't try to break off ice, as you can cause more damage. In the spring, remove the tethers, and your arborvitae will resume its normal shape.
In other instances, the drooping, wilted branches on your evergreen aren't normal. Pine wilt, which is caused by a nematode, afflicts the Scots pine and other pine and evergreen species. The nematode invades the vessels that conduct water from the roots to the top of the tree, preventing water from reaching the foliage and causing it to turn brown and wilt. Brown needles can persist on the tree for extended periods of time, giving the tree a droopy appearance.
If your evergreen isn't drooping because of age or snow, and you suspect pine wilt, then there is no treatment for the disease, according to Iowa State University Extension. Practicing good sanitation prevents many problems. Remove and destroy through chipping any infected trees and branches. Don't save infected trees for firewood, as beetles harboring the pathogen still seek shelter in them and spread the disease.