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Spiny Oak Slug Caterpillar: Stinging Pest on Tomatoes

The bizarre green caterpillar with fleshy spines on your tomato plant is the spiny oak slug—a stinging caterpillar. Its "false legs" exude an irritating liquid that causes painful skin reactions.

Control

Do not touch with bare hands.
Apply Bacillus thuringiensis (B.t.) based caterpillar killer (organic).
B.t. is specific to caterpillars and safe for beneficial insects.

See Guide to Stinging Caterpillars for more information.

Young spiny oak slug (larger ones are as big as the dime pictured)

About Gardening: Why White Oaks Drop Tiny Acorns in Early Summer: The Pollination Story; Oak Bacterial Leaf Scorch: A Fatal Disease with No Cure; Caterpillar Safety: Identifying Poisonous Species and Understanding Their Biology; Identifying Poisonous Caterpillars: What's Safe and What Stings; Gouty Oak Gall: Strange Growths on Oak Trees; Poisonous Trees: Seeds, Leaves, and Acorns; Mothball Toxicity: Naphthalene and Paradichlorobenzene Risks; Finding Reliable Poisonous Plant Resources for Georgia; Planting Ranunculus: Claws Down, But They're Short-Lived Perennials; Are Beautyberries Poisonous? What Gardeners and Parents Should Know

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