Symptom differential
Stem Lesions & Branch-Specific Decline
Localized stem damage can interrupt support or transport and may result from physical injury, pathogens, constriction, insects, or training wounds. Branch-specific symptoms should trigger direct stem inspection.
Pattern questions
- Is decline limited above one stem location?
- Is there splitting, constriction, discoloration, soft tissue, or callus?
- Was the branch recently trained or tied?
- Are insects, frass, or fungal structures present?
Plausible cause categories
- Mechanical injury
- Girdling or tie constriction
- Stem or crown disease
- Boring insect injury
- Severe training damage
- Vascular disruption
Discriminating checks
- Inspect the entire stem below affected foliage
- Remove or loosen constricting ties
- Use magnification around lesions
- Submit samples when a stem pathogen is plausible
Red flags
- Expanding cankers
- Soft or collapsing stem tissue
- Rapid one-sided wilt
- Multiple plants with similar stem lesions
Visual study guide
- Branch-specific symptom locator
- Tie-girdling comparison
- Training wound versus lesion
- Stem cross-section transport diagram