Damage on Pine Tree Trunks

Deer

• Foraging deer can inflict considerable damage to pine tree trunks. During mating season, deer rub their antlers on the bark of the tree, creating an open wound that invites disease, fungi and insect infestation. Deer also browse on tender, new foliage. When deer feast on young seedlings, it can damage the terminal bud tip and the tree may not survive. Protect young trees with wire cages or landscape netting until they are well established.

  The Minnesota Department of Natural Resources recommends using a paper bud cup to protect the bud tip. Purchase bud cups online or you can make your own. Cut a 4-by-6-inch piece of white photocopy paper. Wrap the paper around the bud tip and staple it to the needles. If the terminal bud tip is protected, the tree will continue to grow vertically, even if many of the other branches have been browsed.

Climatic Conditions

• The weight of heavy snow can bend young pine trees, resulting in a bent or deformed trunk. Unless straightened and staked, the tree retains the bent or twisted shape as it matures. Pine trees, growing in locations where they are constantly assaulted by fierce gales, may twist or break from the pressure of the prevailing winds.

Insects

• Boring dust on or at the base of the trunk may be a sign that your tree is infested with pine tree engraver beetles (Ips pini). Brown tree tips is symptomatic of a pine engraver beetle infestation. The European pine sawfly (Neodiprion sertifer) causes deformed trunks and stunted growth in pine trees. The pine sawfly larva exhibits a green body with black stripes and a black head.

Rabbits

• Rabbits girdle a tree. Signs of rabbit damage include removed tree bark and diagonal slash marks left by the rabbit's teeth. If rabbits are a problem in your pine trees, loosely wrap the base of the tree with chicken wire. Wrap to 18 inches above normal snow levels. Rabbits will stand on crusted snow, gnawing higher up on the tree trunk.

Landscape Equipment

• Protect the base of pine tree trunks with a thick layer of pine straw to prevent damage from maintenance or mowing equipment.