Orange Tree Bark Peeling: Causes and Solutions

20+ year-old orange tree shows bark peeling on trunk and major limbs (not at ground level). No black fungus under bark; wood looks healthy. Owner considers wrapping trunk.

Potential Causes

1. Sunburn (Sunscald)

• Common on south/west exposures or after pruning exposes bark
• Citrus bark is thin; intense sun kills cambium
• Bark splits, peels months later

Solution: White latex paint (1:1 water) on exposed trunk/limbs. Reapply annually. Trunk wrap (tree guard) also works—replace yearly for trunk expansion.

2. Fungal Pathogens (Psorosis, Exocortis, Rio Grande Gummosis)

• Often show gumming, oozing, cracking with peeling
• Root-infecting fungi (Phytophthora) cause canopy decline first
• Diagnosis requires lab testing of bark/root samples

Check roots: Excavate several. Healthy = firm, white/cream, abundant laterals. Rotted = dark, sloughing cortex, few laterals.

3. Mechanical/Cultural

• Weed whacker/lawn mower damage
• Improper pruning cuts
• Freeze injury (bark splits on rapid thaw)

Recommended Actions

1. Paint exposed bark with white latex (sunburn prevention)
2. Inspect roots for rot—improve drainage if found
3. Monitor for gumming, dieback, canopy thinning
4. Avoid wrapping with tape—traps moisture, promotes disease
5. Consult citrus specialist if decline progresses

If roots are healthy and no gumming/dieback, sunburn is most likely. Paint protection + monitoring is sufficient.