Colorado Insects of Interest
Order: Coleoptera (Beetles)
Family: Brentidae (Straight-snouted weevils)
Identification and Descriptive Features: Hollyhock weevils are small, gray snout beetles with orange legs. Their most notably feature is their forward projecting snout that is extremely long, particularly on the female. They are common insects found on hollyhock leaves and flower buds throughout much of summer.
Distribution in Colorado: The hollyhock weevil is a native to Europe but now can likely occur throughout the state wherever hollyhock is grown. Distribution of the insect undoubtably has been largely affected by human movement of the insect by transporting infested hollyhock seed so incidence of the insect can be patchy.
As flower buds begin to form, much of the activity shifts to this area of the plant. Mating can very frequently be observed, with the smaller male perched on the back of the female. (Males will also remain with the female to deter other males from mating.) The female uses her very long snout to chew deeply into the developing seed and lays an egg in the cavity. The cream-colored grub then consumes the seed and pupates when feeding is completed.
Management of Hollyhock Weevil in Gardens: Like many weevils, hollyhock weevils will usually drop when disturbed by shaking the plant. They can then be collected and destroyed. Regular removal and disposal of seed pods will destroy developing larvae. Many garden insecticides likely will be effective for controlling adult weevils exposed on plants.
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