Garden Detective

This hungry mystery bug will always be female

Experts tackle readers’ garden questions.

Q: There is an insect that keeps attacking the leaves of my Hawaiian Ti plant. I have removed the pests with tweezers and also used a dish soap solution and a spray bottle but they keep coming back. The pest is about half an inch in length and dark brown in color. Any help in ridding my plant of these would be appreciated. Each summer they attack the plant.

Joseph Sebastian, Sacramento

Sacramento’s “Bug Man” Baldo Villegas: The insect in the photo you provided looks like Fuller Rose Weevil. The females lay their eggs in the soil and the larvae feed on the roots of many types of plants and trees.

Only females are produced and they usually emerge after the larvae feed for 6 to 7 months on the roots of the affected plants.

The weevils should be picked off the affected plants whenever the diagnostic notched damage on the edges of the leaves are noticed. (These notches on the leaf edges start small, but eventually make the leaves look ragged.) There are also some insecticides available for weevil control, but the product label should be read for effective control.

Note: Also known as Fuller Rose Beetle (Naupactus godmani), this snout-nosed weevil reproduces without mating; that’s why they’re all female. Besides ornamental plants, they also like to eat citrus and avocado trees.

These are flightless insects that must crawl up the main stem or trunk of the plant to reach the leaves. Applying Tanglefoot, a sticky form of pest control, to the trunk can catch the weevils before they get to the leaves; it’s available at most nurseries.

For more information on Fuller Rose Weevil, check out the University of California’s Integrated Pest Management website (ipm.ucanr.edu) and look for “Fuller Rose Beetle.”

Retired state environmental researcher Baldo Villegas is a master consulting rosarian and longtime insect expert.

Garden questions?

Questions are answered by master gardeners at the UC Cooperative Extension services in Sacramento and Placer counties. Send questions to Garden Detective, P.O. Box 15779, Sacramento, CA 95852. Send email to h&g@sacbee.com. Please put “Garden Detective” in the subject field and include your postal address. To contact UC Extension directly, call:

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