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Light Green Growth on Pineapple Guava Trunk: Likely Lichen

Identification

Light green "fungus" at the base of a pineapple guava in a raised bed is probably lichen (algae + fungus). Lichens can appear greenish depending on algal component. They are harmless, using bark for support.

Confirmation

Compare to lichen photos online (leaflike, curly edges, filamentous, small cups). If it matches, no action needed. Mulch decomposition fungi are also normal and beneficial.

Plant Diseases: Hypoxylon Canker on Green Ash: Signs and Management; Elm Trunk Lichens: Harmless Epiphytes Indicating Thin Canopy; Blue-Gray Growth on Tree Trunks: Lichens—Harmless, Indicate Light, Not Cause of Fruit Tree Decline; Green Fungus Killing Sweetgum Trees: Likely Lichen or Algae, Not Fatal; Greenish-White Scale on Oak: Lichens, Not a Disease; Black Trunk on Live Oak: Natural Aging or Lichens?; Lichen on Flowering Crabapple: Harmless Indicator of Tree Stress; Green Growth on Black Walnut Branches: Lichens, Not Disease; Gray Fungus on Large Trees: Lichens, Not a Disease; Lichens on Dogwood: Harmless but Check for Other Tree Issues

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