You may have noticed the browned white pine trees in our area, especially along 19E near Bald Creek. What you are seeing is the effects of Pitch canker which is a widespread fungal disease that can lead to death in many pine species in North Carolina. Longleaf, loblolly and slash pine are most commonly affected, but the disease can impact any southern pine.
While it is typically not common, pitch canker is prevalent on white pine in western North Carolina this year. It is primarily observed on trees along forest edges, but as the season progresses, it is likely to impact others.
“Heavy amounts of rainfall and cooler temperatures are ideal conditions for pitch canker, which are likely the reasons for the increased prevalence of pitch canker this year,” said Brian Heath, a forest health specialist with the N.C. Forest Service.
Pitch canker causes infections that encircle branches, exposed roots and main stems. This infection creates cankers from which resin or pitch accumulates. The tips of branches wilt due to less water flow, and needles turn yellow and then brown. Eventually, needle clusters may fall off, leaving bare branch ends. Other symptoms include:
Dieback of the tree, which can eventually lead to death.
Slow tree growth.
Diseased bark, which is tan to chocolate brown colored. Removal of the bark exposes
yellowish sapwood that is resin-soaked.
Infected trees are often attacked by engraver beetles, which cause additional death in
the branches of the trees.
The fungus can also kill cones and seeds.
Wind or insects carry spores produced by pitch canker to new trees. “Damage caused by severe weather or insect feeding make pine trees more susceptible because they create wounds on the tree through which spores may enter,” Heath said.
Little can be done to prevent or treat pitch canker. Avoid wounding trees since the fungus may enter through lesions. “In certain situations, proper tree care can also help trees overcome the infection,” he added. There is no effective fungicide treatment for pitch canker. While pitch canker can cause death, not all infected trees become severely diseased, and some may recover.
Because recovery is possible, use a conservative approach to removing diseased trees. Removing symptomatic branches may help improve the aesthetic of the trees.
If you believe that your trees have signs or symptoms of pitch canker, contact your N.C. Forest Service County Ranger for correct identification and advice. You can find your County Ranger by visiting http://www.ncforestservice.gov/contacts/contacts_main.htm.
