Extension > Garden > Diagnose a problem > What insect is this? > Trees and shrubs > Caterpillars, maggots, grubs, and similar immature insects - 1 to 2 inches long > Spiny elm caterpillar
Spiny elm caterpillar
Nymphalis antiopa
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Jeff Hahn, University of Minnesota Extension
Description: 2 inches long. Dark colored body, peppered with white spots, eight red spots running along top of body and armed with black thorn-like spines.
Where/When: Prefers elm and willow; also, attacks hackberry, poplar, aspen and birch. Present May to June and again in July to August.
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