Pine tree deterioration

Asked October 21, 2019, 6:21 PM EDT

Pine trees needles are tuning brown and appear to be dying. Black mold or growth is seen on the trunk of the tree. Pruned top of one pine because it had died. Hope there is something I can do to mitigate damage.

Berrien County Michigan

3 Responses

Unfortunately, I don't think there is anything you can do to save the tree. I think the black, gnarly areas in your photos are cankers. Cankers are caused by a fungus which can girdle the branch or trunk, thus inhibiting water and nutrient movement. Since the cankers are occurring on the trunk this will more than likely eventually kill the tree. Resin may flow out of the cankers and may drip down on lower branches.Fungicide sprays are not effective and are not recommended because they will not cure trees showing decline symptoms. The yellowing foliage could be due to spider mite damage or be related to the canker.

Thank you for your response. Is there anything I can do to protect neighboring trees?

Keep plants healthy and vigorous.

  • Reduce stress on spruce trees by providing water during periods of drought.
  • Mulch the soil beneath the tree.
  • Check spruce trees once a year for cankers.
  • Prune out and destroy infected branches during dry weather.
  • Avoid all unnecessary bark wounds, because many pathogen’s main entry is through injuries.
Here is some more information on cankers in trees from Cornell.