How to stop earwigs and coreopsis beetles: Ask an expert – oregonlive.com

When you have gardening questions, turn to Ask an Expert, an online question-and-answer tool from Oregon State Universitys Extension Service. OSU Extension faculty and Master Gardeners reply to queries within two business days, usually less. To ask a question, simply go to the OSU Extension website and type in a question and the county where you live. Here are some questions asked by other gardeners. Whats yours?

Earwigs tend to feed at night and hide during the day.OSU Extension Service

Q: The annuals we planted a couple of weeks ago at our residential home in Bend have been eaten by something. We have tried three different recommendations, including slug bait, insecticide powder, as well as a spray. Nothing seems to be helping. No visible insects during any daylight hours. Any ideas on what is causing this and recommendations to get rid of them would be greatly appreciated. We did plant the same types of annuals at the same time last year and had no issues. Deschutes County

A: Without actually seeing an insect feeding on your plants I cannot be positive but this looks like earwig damage. They tend to feed at night and hide during the day. You could try to put out traps of rolled, moistened newspaper with a couple of drops of fish oil in the middle of the roll. This will entice earwigs to go into the newspaper which you should discard into the trash daily. Another trap for earwigs is a small can (like a tuna can) placed in the ground so the top is even with the soil line. Place a little water (not more than half full) with a couple of drops of fish oil in the can and a drop of non-fragrant dish soap. This will trap the earwigs too. These traps may catch other insects that may be the culprits if not earwigs. If you do find that earwigs are caught in the traps, a chemical solution is Sluggo Plus that is labeled for earwigs. I'm sorry your flowers were eaten. I hope you can trap the insect so you learn what is doing the damage. Toni Stephan, OSU Extension horticulturist

These are lady beetle larvae (ladybugs).OSU Extension Service

Q: We found many of these creatures lining the pavement at the base of our garage door. Can you identify it for us? I personally looked through 501 bugs of Oregon and through what I could find on the OSU site. I found nothing resembling them. We just want to make sure they are harmless to our plants and home. Lane County

A: These are lady beetle larvae (ladybugs). We love these guys and their voracious appetite for eating other insect that eat our plants, and they are so cute in all their life stages. Chrissy Lucas, OSU Extension small farms specialist

The coreopsis beetle (Calligrapha californica) only feeds on coreopsis, sometimes called tickseed.OSU Extension Service

Q: I just found a few of my plants that are covered in an insect that looks like a striped ladybug. They appear to be eating the leaves of the plant, and they seem to be isolated to this specific plant. Are they harming the plant? How can I get rid of them if they're not going to be beneficial? Washington County

A: The insect is the coreopsis beetle (Calligrapha californica) and it only feeds on coreopsis, sometimes called tickseed.

Both the larvae and adults feed on coreopsis. They seem to be periodic pests, gobbling coreopsis for a year or so, then no activity at all.

You must act quickly because these beetles will rapidly reduce the plant down to shreds. Direct hits of a commercial insecticidal soap will get rid of the soft-bodied larvae whereas the adults must be handled more directly flick them into a cup of soapy water. Don't use a homemade concoction of soapy water as it's likely to further damage the plant.

For text and images about coreopsis beetles, go here. To see the images, you may need to click each empty box, which is an icon for an image. Jean R. Natter, OSU Extension Master Gardener diagnostician

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How to stop earwigs and coreopsis beetles: Ask an expert - oregonlive.com