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Gummosis on Ornamental Plum: Insect Wounds and Sap Flow

Jelly-Like Globs Are a Defense Response

The gelatinous globs dripping from your ornamental plum branches are plant sap (gummosis) produced in response to injury—most often an insect puncture. The sap seals the wound and deters further feeding.

Next Steps

Examine the bark under the ooze for entry holes or frass.
If an insect is confirmed, take a sample to your local garden center for specific insecticide recommendations.
Prune out heavily damaged branches to reduce stress.

Healthy trees can compartmentalize these wounds and continue thriving.

Plant Diseases: Plum Tree Shot Hole and Bark Bumps: Separating Insect Damage from Normal Lenticels; Ornamental Plum Chlorosis: Iron Deficiency or Soil Problem?; Plum Tree Leaf Curl and Eggs: Beneficial vs. Pest Identification; Plum Tree with Raised Bark: Black Knot Disease; Ornamental Plum Delayed Leaf-Out: Environmental Stress vs. Fatal Decline; Plum Tree Loose Bark with Magenta Spores: Complex Diagnosis Needed; Black Knot on Ornamental Plum: Organic Atomic Grow Treatment; Plum Tree Soft Bark Bumps: Scale Insect Infestation; Plum Pocket Disease: Remove Fruit, Fungicide Next Year; Plum Tree Leaf Spot and Fruit Drop in New Zealand

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