Greenish-Silver Patches on Maple Bark: Lichens, Not a Killer

Maple cut down after developing greenish-silver patchy growth on limbs. These were lichens—symbiotic algae+fungi, epiphytic (not parasitic).

Lichen Facts

• Three forms: crustose (flat), foliose (leafy), fruticose (shrubby).
• Indicate clean air, high humidity, thin canopy.
• Slight negative effect (shade reduction), but mostly cosmetic.
• Control: improve tree vigor → denser canopy → less light → lichens decline.

Don’t Use Baking Soda Sprays

Not needed. Fertilize (1 lb 10-10-10 per inch DBH), mulch, water. Lichens signal thin canopy, not cause it.

Tree removal was unnecessary for lichens alone.