Green Growth on Maple Trunks: Lichen, Not a Killer

Medium green growth on maple trunks (October Glory, Schwedler) for years, with bark peeling on one tree, is lichen—a harmless air-fed organism. It did not kill the nearby Bradford pear.

Why Lichen Grows

• Thrives on sunny, exposed bark (thin canopies, winter).
• Indicates, but does not cause, tree stress.
• Wet = active growth; dry = dormant.

No Removal Necessary

Lichen takes nothing from the tree. Peeling bark on Schwedler maple may be natural exfoliation or stress-related—not lichen damage.

If You Must Reduce It

• Copper fungicides (for ball moss) may suppress lichen.
• Baking soda spray (home remedy) can help.
• Pecan orchard scab fungicides reduce lichen as side effect.

Best: leave it. It’s a sign of clean air and adds character.