Dealing with Winter Damage on Trees and Shrubs

OLYMPUS DIGITAL CAMERAWinterburn:  When needles/foliage of evergreens brown out in late winter/early spring the conditionb is called winterburn.  It is caused by overly harsh winter sunlight, most notably from sunlight reflecting off snow banks in January, February, and March.  With light to moderate winterburn new growth will emerge in May/June and once again give the evergreen shrub or tree a nice appearance.  Some of the brown needles may fall off the plant which happens when enough of the needle dies to cause it to shed.  Usually the twig stays alive, enabling new growth to take place.  In cases of severe winterburn some twigs and or small branches may die.  Completely dead twigs/branches should be carefully pruned off, being sure to leave all plant parts that are still alive.  Pruning away dead material will create an open area into which the plant can now send new growth and more rapidly achieve a pleasing appearance.

Mouse and rabbit damage:  Desperate for food during a long, hard winter, mice and rabbits will sometimes eat away the bark in some areas.  When this happens, water, sap, and nutrients cannot move well enough to certain branches to keep those branches alive, and the branch or twig or top part of the plant may die.  Good prevention methods are reduction of mouse and rabbit populations, surrounding plants with cylinders of ¼” mesh galvanized hardwire cloth, and putting white plastic tree guards on the lower part of the main stem.  If the bark is eaten away all the way around the main trunk, start to make plans for a replacement, or prepare to cut the plant back fairly aggressively so that all the damaged areas are all removed, and new sprouts/stems and foliage production will be stimulated.  Avoid leaving dead parts on plants you hope to enjoy in the future.  Fertilize regularly, but not excessively following corrective pruning.

Deer antler rubbing damage:  Carefully trim off ragged/loose/cupping/curling bark or twigs.  Fertilize moderately to allow new bark to grow over the wound which may take 2-5 years.  Each fall install a white plastic tree guard to prevent future antler rubbing damage.  Remove the tree guards the following spring when the grass turns green.  Be sure to use white tree guards, not with dark colors.