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Black Lines in Lightning-Struck Maple Wood: Lightning Trace Scars—Fascinating Wood Feature

Maple cross-section with fine black lines

Cause

Fine black lines = lightning trace scars. Lightning travels unpredictably—sometimes leaves tree intact but marks interior. Insect borers make coarser holes.

Value

Wood with lightning figures is prized for conversation pieces. Save some!

Plant Diseases: Sugar Maple White Spots: Harmless Lichens, Real Issue Likely Planting or Herbicide; Black Spots on Sugar Maple Trunk: Borers or Bleeding Canker?; Mysterious White Foamy Growth on Maple Trunk: Not Slime Flux; Sugar Maple Yellow Fungus and Black Leaves: Disease Overview; Black Spots on Japanese Maple Bark: Likely Harmless Lichens; Black Spots on Maple Leaves: Tar Spot Fungus—Rake Leaves, Reduce Inoculum, Tree Usually Fine; Maple Tree Black Eggs: Gall Mites, Not Eggs; Maple Leaf Galls: Insect-Caused Bumps on Autumn Blaze Maple; Black Trunk on Young Sugar Maple: Normal Bark Maturation; Maple Tree Black Ooze: Slime Flux (Wetwood)—A Mixed Blessing

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