Please identify this beetle

Question: These beetles used to appear in my house (in one or two rooms) for a few weeks every spring. Now they’re showing up in all rooms year-round. What are they and how do I get rid of them?

responder: An Ask Extension Expert Replied March 24, 2023, 7:23 PM EDT
response: The insects you have are beetles, it is hard to say if you have carpet beetles, storage pest beetles or wood boring beetles. It would be helpful if you could examine your food storage area such as a pantry for any signs of an infestation in the food packages. The other type of beetle carpet beetles can damage items such a any products that have dried organic parts such as wool clothing, furs, dried flower arrangements, feathers as examples. The last kind are wood boring beetles, The damage they cause are to wooden furniture where they leave fine power where they bored into wooden furniture. I have attached a publication on these three types of beetles. If you can, read them and let me know if one matches the problem you have with these beetles. That you are finding them all year around means you need to try managing this pest ASAP. Let me know if you have any additional questions. Rich

responder: The Question Asker Replied March 27, 2023, 8:29 PM EDT
response: Hi Rich, Thank you so much for sending this information—it is extremely helpful. Except that I don’t think any of these are the beetles I have. I’ve definitely ruled out the carpet beetles--my beetles don’t look anything like any of the three that are shown in Pub 7436. For one thing, my beetles do not have short antennae, their antennae are long. I’ve also ruled out the various kinds of pantry beetles. For one thing, my beetles are tiny compared to those shown as "actual size.” For another, I have zero evidence of infestation in any of my food storage areas, and believe me, I checked very carefully! So that leaves the powderpost beetles. At first I thought they might be a possible candidate, especially because the upstairs room where my beetles are most pronounced, and in which they appeared first, is completely paneled in wood! However, close reading of PNW 326 leads me to the conclusion that they are not my beetle. My beetle is medium brown with an almost greenish tint; its body is definitely not "dark brown to nearly black" (lyctidae), or "reddish-brown to nearly black” (anobiids and bostrichids). My beetle has antenna that are very skinny and very long, almost a third as long as its head/body; its antenna do not look like any of the pictured antenna. My beetle has gold-colored legs. I do not see any exit (emergence) holes in the wood, nor any powdery frass.I am wondering what to do next. I wouldn’t be concerned because I’ve always just vacuumed them up when they showed up every spring (this has been going on pretty much ever since I moved in 40 years ago). But now, I’m seeing them all year round (though not in the great numbers I see every spring). And, as I mentioned, they are now for the first time showing up in other parts of the house, including a few downstairs! Would it be possible to gather some and bring them down to show you? I really don’t want to “employ a professional…insecticide or fumigant” unless I have to. If that’s what you think I should do, do you have any suggestions for what kind I should buy? Many thanks for your help!Cathleen SmithOn Mar 24, 2023, at 4:23 PM, Ask Extension <<personal data hidden>> wrote:

responder: An Ask Extension Expert Replied March 28, 2023, 12:48 PM EDT
response: Your note does not surprise me. Those three groups are the most common pest found in a house. This will make it more challenging to figure it out because most likely pest now is coming from outside. Seeing the beetles will answer this. You can take the samples to your local Extension office to see if anyone there can ID them. If not, maybe we can get the specimens to me.

responder: The Question Asker Replied May 23, 2023, 12:07 PM EDT
response: I’ve done more research, and I believe what I have are elm leaf beetles. Please send me any information you have about how to deal with them in Oregon. I’ve read the reports about this beetle from other states, but would very much appreciate knowing what the local experts recommend with regard to this beetle. Thank you! Cathleen SmithSent from my iPad On Mar 28, 2023, at 9:48 AM, Ask Extension <<personal data hidden>> wrote:﻿

responder: An Ask Extension Expert Replied May 23, 2023, 7:01 PM EDT
response: Just received your note and it was a surprise. If these are Elm leaf beetles and you stated earlier this has been going on for 40+ years (Is this correct?). They have been coming in from outside all this time. That you are seeing them all year long is what lead me to believe they were an internal pest. My question is, do you or your neighbor have Elm trees. I am not sure you have Elm tree beetles but have attached a link to information on control. Elm (Ulmus)-Elm leaf beetle | Pacific Northwest Pest Management Handbooks (pnwhandbooks.org) Let me know if you have additional questions. Thank you for letting us help you. Rich

responder: The Question Asker Replied May 24, 2023, 12:23 PM EDT
response: ﻿Rich, thank you so much for your quick response. I plan on taking some of my beetles to the Washington County Extension service tomorrow to confirm my suspicions. My beetles look exactly like the pictures of elm leaf beetles on the web, except mine are not yellow but a green-tinged medium brown color.  I wish the link you sent me had information about what to do if they are actually in your house. I understand from other publications that basically I should caulk crevices, cracks, and holes around the windows where I see the most beetles.  For me, this means just two windows. (I wasn’t entirely accurate when I complained I was seeing them everywhere in the house. I have them in great numbers in only two adjoining rooms). Do you have any idea what time of year this caulking should be done? The numbers of beetles are really dying down at this point, is this when I want to do it? Or later in the summer?I don’t have an elm tree in my yard, but I’m guessing there’s one in the neighborhood because my neighbor has the same problem (I’m not sure what elm trees look like, so that’s a problem). Anything you can tell me about the best timing for my sealing/caulking would be greatly appreciated. Thanks so much for your help.CathleenSent from my iPadOn May 23, 2023, at 4:01 PM, Ask Extension <<personal data hidden>> wrote:﻿

responder: An Ask Extension Expert Replied May 24, 2023, 7:00 PM EDT
response: Cathleen: I have put together the following which I hope will help you keep the beetles out. NON-CHEMICAL PEST CONTROL & MANAGEMENT Any cracks, crevices or voids present in the structure can provide a space for the pests which provides safety/protection. Potential sites within a structure include crawlspaces, wall voids and attics and any other space existing within the structure. If these spaces have not been protected from the elements with vapor barriers, proper ventilation, and protected from leaks, if this space also provides a food and/or water source, this is where pests will not only survive but reproduce as well.  Other voids that can be found in structures are spaces that can be found between dishwashers and kitchen cabinets, refrigerators, the space behind baseboards, the area between built-in cabinets and the wall, inside appliances and furniture, or gaps on the exterior cladding. Where possible these Structural voids should be made unusable by sealing the cracks, crevices, and other pathways through these voids.  In addition to sealing cracks, and voids found within the structure you can do the following to keep pests from entering your home. Install door seals on all exterior doors, properly fitted screens on all windows. Doors and windows must be well-sealed when closed, and that all foundation and attic vents are adequately screened, sealed, and operating properly to keep the pests out. These maintenance procedures should be performed any time of the year that you discover them. Various beetles can overwinter indoors, such as in attics and wall voids. Repair and caulk openings near elms. Remove by hand with vacuum or by sweeping up; dispose of beetles outside.  There are no traps or pesticides for specific use on these beetles. Let me know if you have additional questions. Thank you for letting us help you. Rich

responder: The Question Asker Replied May 25, 2023, 5:57 PM EDT
response: Hi again, Rich,Just got the call from the OSU Extension Service Master Gardener, who confirmed that my beetles are elm leaf beetles. She agreed that sealing/caulking the windows where they are coming in is a possible solution, but I forgot to ask her when I should do that. It seems to me that I should do it now that the vast majority of them have left the house, but before they start coming back inside the house. Do you agree? Do you happen to know when they will start coming back in? Thanks for any information you can provide. CathleenSent from my iPad Begin forwarded message:From: Cathleen Smith <<personal data hidden>>Date: May 24, 2023 at 9:21:02 AM PDTTo: Ask Extension <<personal data hidden>>Subject: Re: Please identify this beetle (#0092964)﻿﻿Rich, thank you so much for your quick response. I plan on taking some of my beetles to the Washington County Extension service tomorrow to confirm my suspicions. My beetles look exactly like the pictures of elm leaf beetles on the web, except mine are not yellow but a green-tinged medium brown color. I wish the link you sent me had information about what to do if they are actually in your house. I understand from other publications that basically I should caulk crevices, cracks, and holes around the windows where I see the most beetles.  For me, this means just two windows. (I wasn’t entirely accurate when I complained I was seeing them everywhere in the house. I have them in great numbers in only two adjoining rooms). Do you have any idea what time of year this caulking should be done? The numbers of beetles are really dying down at this point, is this when I want to do it? Or later in the summer?I don’t have an elm tree in my yard, but I’m guessing there’s one in the neighborhood because my neighbor has the same problem (I’m not sure what elm trees look like, so that’s a problem). Anything you can tell me about the best timing for my sealing/caulking would be greatly appreciated. Thanks so much for your help.CathleenSent from my iPadOn May 23, 2023, at 4:01 PM, Ask Extension <<personal data hidden>> wrote:﻿

responder: An Ask Extension Expert Replied May 25, 2023, 6:22 PM EDT
response: I would do the sealing/caulking now. As for any that may still be inside you can get rid of them knowing you have sealed the house. Rich