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Japanese Maple Yellow Spots: Environmental Stress, Not Disease

Transplanted homegrown Japanese maple shows yellowish raised spots on leaf edges. Mother tree has fewer spots. Photo attached.

Diagnosis: Environmental, Not Pathogenic

Spots not a recognized infectious disease. Uniform edge browning often indicates root stress from past drought. Temperature fluctuations or transplant shock can cause similar symptoms.

Cultural Practice

Rake and dispose of fallen leaves in late winter before bud swell to reduce pest/disease carryover. Maintain consistent moisture. No spray needed.

Plant Diseases: Japanese Maple Honeydew and Sooty Mold: Aphid or Scale Infestation; Japanese Maple Transplant Shock and Leaf Scorch; Southern Magnolia Excessive Leaf Drop: Check for Root Stress; Orange Growths on Japanese Maple Bark: Scale Insects, Not Disease; Managing Borers in a Mature Japanese Maple; Crepe Myrtle Yellow Leaves: Heat, Drought, or Nutrient Imbalance; Plum Tree "Ghost Leaves": Diagnosing Browning and Bud Check; White Powder Under Lemon Leaves: Early Powdery Mildew or Something Else?; Japanese Maple Lost All Leaves After Planting: Shock or Deer?; Japanese Maple Freeze Damage: Scratch Test, Wait, Then Prune

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