Saucer Magnolia with black bark demage and branch death - Ask Extension
What can be done? We have not done anything for this tree.
Knowledgebase
Saucer Magnolia with black bark demage and branch death #923746
Asked January 18, 2026, 1:10 PM EST
What can be done? We have not done anything for this tree.
Montgomery County Maryland
Expert Response
We can't see enough detail in the photos to diagnose the tree, especially as the first two images are too dark. The third image is showing some lichen on the bark, which is normal, natural, and harmless, though we don't see the cracks you mention. What indications are you seeing of branch death this time of year? (Are there some branches that lost leaves well before autumn last year, which have no buds on the branch tips currently?) We see lots of flower and leaf buds on the tree, which would indicate that those branches are likely alive, unless the buds desiccated but haven't fallen off yet.
If there is black residue coating the bark, it might be sooty mold, which is a fungus that grows on honeydew. You can learn about both on the linked page, but since the sooty mold doesn't infect the tree and only causes aesthetic problems, no remedy is needed (nor would applying a fungicide help much). It will weather off on its own once the presence of honeydew abates, and that will happen when whatever insect is producing it has its population reduced. Scale insects are a possibility (Magnolia Scale or Tuliptree Scale, potentially), but last year's Spotted Lanternfly adults may be more likely.
Tree health concerns, especially with mature trees, should be addressed by a certified arborist or licensed tree expert who can both narrow-down a diagnosis and potentially use a pesticide to treat certain problems, when warranted. (Not all pesticides are legal for someone that doesn't hold a pesticide applicator's license to apply. Some may also risk harm to pollinators visiting a treated plant's flowers.) Fortunately, both Spotted Lanternfly and soft scale insects (like the two species noted above) generally do not cause serious or long-lasting damage to the tree, and their honeydew (and the resulting sooty mold) is just a nuisance. Soft scale outbreaks generally do not kill the host tree, but if they are contributing to tree stress and branch dieback, then one or more insecticides may be needed to knock back the population. You can learn more about their appearance, life cycle, and management options in the scale pages linked above.
Miri
If there is black residue coating the bark, it might be sooty mold, which is a fungus that grows on honeydew. You can learn about both on the linked page, but since the sooty mold doesn't infect the tree and only causes aesthetic problems, no remedy is needed (nor would applying a fungicide help much). It will weather off on its own once the presence of honeydew abates, and that will happen when whatever insect is producing it has its population reduced. Scale insects are a possibility (Magnolia Scale or Tuliptree Scale, potentially), but last year's Spotted Lanternfly adults may be more likely.
Tree health concerns, especially with mature trees, should be addressed by a certified arborist or licensed tree expert who can both narrow-down a diagnosis and potentially use a pesticide to treat certain problems, when warranted. (Not all pesticides are legal for someone that doesn't hold a pesticide applicator's license to apply. Some may also risk harm to pollinators visiting a treated plant's flowers.) Fortunately, both Spotted Lanternfly and soft scale insects (like the two species noted above) generally do not cause serious or long-lasting damage to the tree, and their honeydew (and the resulting sooty mold) is just a nuisance. Soft scale outbreaks generally do not kill the host tree, but if they are contributing to tree stress and branch dieback, then one or more insecticides may be needed to knock back the population. You can learn more about their appearance, life cycle, and management options in the scale pages linked above.
Miri
