Home and Landscape

Sunflower Stem Weevil

  • Cylindrocopturus adspersus
Updated: 01/2025

Identification

Sunflower stem weevils are pests of sunflowers. Adult beetles are dark brown with light spots and about 1/8-inch long. Larvae are pale maggots.

Damage

Larvae bore in stalks and overwinter in lower stalks and crowns. Foliage yellows and wilts. Plants fall over.

Solutions

Consider delaying planting; many beetles will emerge and die before laying eggs. Deeply incorporate or remove and dispose of debris. Consider planting other plants. Avoid broad-spectrum insecticides; parasites may help to control beetles.

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