Rhubarb Curculio identification

Organic Control Profile

Rhubarb Curculio

Lixus concavus

9
Plants Affected
3
Natural Enemies
5
Control Strategies

A long-snouted weevil that punches feeding holes in rhubarb stalks and dock leaves, leaving sap spots and inviting rot—think of it as a cocktail pick with commitment issues. Adults migrate from wild hosts in spring.

Dark weevils about 8–10 mm with a slender rostrum; feeding scars appear as rows of punctures on petioles. Larval development is mainly on curly dock and other weeds, not inside rhubarb hearts.

More identification photos — verified field observations

Organic Control Methods

Organic Sprays

Pyrethrin or neem on stalks and surrounding dock patches during adult activity—focus evenings when weevils climb; repeat after rain.

Biological Controls

Birds, predatory beetles, and spiders pick off adults; parasitic wasps attack some Lixus larvae in stems of wild hosts.

Cultural Practices

Mow or remove nearby curly dock and sorrel before adults move to rhubarb; harvest stalks promptly; avoid leaving split stalks that hold moisture.

Mechanical & Physical

Shake adults into soapy water on cool mornings; row cover early spring clumps before migration peaks.

Prevention

Scout margins between rhubarb and wasteland; rotate harvest from outer rows where immigration hits first.

Natural Enemies

Plants Affected — 9 in Database