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Leaf-Eating Insects: Aphids, Beetles, and Millions More

Insects eating leaves use diverse strategies: aphids suck sap, Japanese beetles chew tissue, caterpillars consume blades. Over half of insect species feed on plants.

Major Groups

Sap-feeders: Aphids, scales, whiteflies (piercing mouthparts).
Chewers: Beetles, caterpillars, grasshoppers (mandibles).
Miners/borers: Inside leaves/wood.

Diagnosis

Identify damage pattern, then match to pest. Photos help.

Pests: Holly Scale Infestation: Oil or Systemic Insecticide; Scale or Powdery Mildew on Lilac: Neem Oil vs. Atomic Grow; Black Sooty Mold on Holly: Control the Sucking Insects First; Sooty Mold on Camellia Hedge: Caused by Scale Insects; Sudden Black Bugs on Ceiling + Green Caterpillar in Lamp: Likely Unrelated; Butterfly Bush Lace-Like Leaves: Identify Damage Before Treating; Should You Remove Insect-Damaged Rose Leaves?; Identifying and Treating Insects on African Violets; Drosera adelae Leaf Damage After Prey Capture: Normal Behavior; Holly Scale Infestation: Identification and Treatment Plan

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