Where Did All These Japanese Beetles Come From?

Sow_what? Southern California InlandAugust 7, 2014

And will anything be left our roses by the time they're gone? Is anyone else having this problem?

Thank you for reporting this comment. Undo
rideauroselad E.Ont4b


The direct link with this post is to a Purdue University fact sheet on JB's with a map of infested areas as of 2011. As of that year, there were a couple of counties in central California where the linked map shows that eradication efforts were in effect, the rest of the state and Southern California in particular are shown as JB free.

State, Provincial and federal governments in both the US and Canada run extensive trapping surveys in non infested areas each year. But the spread of this insect continues from the point of establishment in New Jersey in 1916. There is no stopping it, only slowing it down.

The introduction and spread of exotic pests in nothing new, man is an extremely good vector. Our commerce and our individual desires for goods and yes, plants that come from other places has long spread invasive species far and wide. That is why there are regulations, both internationally and domestically about the movement of plants and plant material and often phytosanitary requirements for movement of these things even between counties at times. As gardeners who acquire sought after plants, we especially, have a duty to educate ourselves about these issues and make sure we are not part of the problem.

The area where I live is JB infested, but the critters remain mostly in the larger agricultural field areas and in the City of Ottawa to the North. I was at the rose garden at the Central Experimental Farm in Ottawa in early July and many of the roses were being chewed to pieces.

I have seen one JB on my plants so far this year and have
never had a major infestation since moving here 12 years ago. But then the town where I live is surrounded by forest and lake, which seems to act as a buffer zone.

The link pasted here:


is from an appendix to the Canadian government fact sheet on JBs and is a very good chart summary of infested and non infested provinces and states in both countries. It too is from 2011 and lists California as a non infested state.

You may wish to check with your State extension agent to find out the status in your county and the State. If it is a recent infestation, there are likely eradication efforts going on. I pray that they are successful.

Cheers, Rick

Here is a link that might be useful: Japanese Beatle, North America Origin, Distribution

    Bookmark   August 7, 2014 at 8:39AM
Thank you for reporting this comment. Undo

I had never seen a number of japanese beetles till this year. This year, one of my pest plants that I've tried to eradicate without success for 30 years, is the target. I haven't tried to control the beetles at all, and I haven't seen them on any other plant. The bad thing is I know, all those larvae that will come from the adults, will make 'war' another year, perhaps on a more desired host.

    Bookmark   August 7, 2014 at 8:44AM
Thank you for reporting this comment. Undo
michaelg(7a NC Mts)

I think, living in a semi-desert, you would only have JB problems if you live near a golf course or other large area of irrigated turf, or perhaps cropland that is irrigated in summer and early fall. The adults lay eggs in summer, and the young larvae need moist soil in order to move around and feed.

Have you got a positive ID, as opposed to hoplia beetle, asiatic beetle, etc?

    Bookmark   August 7, 2014 at 9:56AM
Thank you for reporting this comment. Undo
Sow_what? Southern California Inland

Can someone ID if I post a picture?

    Bookmark   August 7, 2014 at 11:28AM
Thank you for reporting this comment. Undo
ingrid_vc(Z10 SoCal)

This really shocked me; I had no idea they were in California. In this respect I feel fortunate that I live on a barren hillside. After seeing pictures of roses being covered with these beetles, I don't know if I could stand having roses if they arrive here. That would probably be the coup de grace to my ever more challenging efforts to grow roses. I pity everyone who has to put up with this awful pest.


    Bookmark   August 7, 2014 at 1:24PM
Thank you for reporting this comment. Undo

Hopefully you don't have Japanese beetles, as they are a terrible pest.
The grubs eat the roots of grasses and the beetles eat the leaves and blooms off of roses and other plants that they find tasty.
Hand picking them and killing them might be better than using attractant traps, which will attract more beetles to your yard.
Below is the Wikipedia page about Japanese beetles, complete with pictures.
They're almost pretty, but I hate what they do to plants.
FWIW, if you have pet chameleons-- and can be sure your beetles haven't been poisoned-- the chameleons will enjoy eating these beetles.
If you post a picture, someone will surely be able to ID the beetle.

Here is a link that might be useful: Japanese beetles

    Bookmark   August 7, 2014 at 2:21PM
Thank you for reporting this comment. Undo
Sow_what? Southern California Inland

Crazy day and didn't get back to the garden 'till after dark when too late to catch or ID, but I did observe significant damage to the figs on our fig tree, and damage to the rose foliage in the main rose garden. There were almost no blooms to damage since those had been knocked off during last weekend's pelting rainstorm, or removed by me right after.

Rick, thanks so much for the information. I've been purchasing all plants locally lately, except roses. Plants purchased from afar have had phyto cert and sometimes ag inspection as well. I called extension for Riverside and San Bernardino counties, but have not heard back yet. What I did bring in late last year was a lot of mulch from local tree trimmers.

Dbarron, I wish you the best of luck. I sure hope what we have here isn't Japanese Beetles.

MichaelG, we don't have a stitch of turf here, but we're across the street from the university/medical center, where the multi-acre campus is carpeted in overly irrigated turf. I was first shown this "Japanese Beetle" on an acre plus property that's landscaped with well if not overly irrigated turf with significant brown patches. The beetle I was shown was metallic green and metallic bronze, and perhaps just a bit smaller and more rounded than what we call "June Bugs". Just yesterday as I was rushing through, I thought I saw swarms of these same beetles at Humpty Dumpty House, in our fig tree, our cumquat tree, and our main rose garden. I did not have time to catch one to try to make a positive ID, but it was metallic green and bronze, and looked like the same beetle I had been told was JB. I sure hope I'm wrong. I'm pretty certain it was not a hoplia or asiatic beetle.

Ingrid, I apologize; I didn't mean to cause alarm. I'm afraid I kind of panicked when I saw swarms of beetles in our fruit trees and roses when I couldn't stay or get back in time to do anything about it. It didn't help that the mulch we brought in came from the property where I was shown the "JB". I just pray that's not what we have. I was shocked at the amount of damage; every one of our figs was reduced to an empty sack, and some of our roses looked liked they'd been ravaged with craft scissors.

Lazybonz, thanks for the info -- will try to get photo in the light of day. Too tired to read link, but photo does NOT look same color as the "JB" I was shown, or the beetles swarming at HDH. Same form, but our beetles are metallic green and bronze -- not black like this photo, so hopefully these are something else.

    Bookmark   August 8, 2014 at 6:35AM
Thank you for reporting this comment. Undo

Actually mine are almost identical to junebugs too, but about half the size, which correlates completely with Japanese Beetles.

    Bookmark   August 8, 2014 at 7:11AM
Thank you for reporting this comment. Undo
rideauroselad E.Ont4b


Irrigated turf, brown circles; "The beetle I was shown was metallic green and metallic bronze, and perhaps just a bit smaller and more rounded than what we call "June Bugs"....

This sounds very much like a JB infestation to me.

I found a web page from the California Department of Agriculture with their JB profile sheet and have linked to it. There are very good images of grubs and a size and species comparison with June Bugs. The web page says there have been 3 infestations in your state thus far, all successfully eradicated. The page has a date of June 20th 2014 at the bottom. So it is quite possible that you have discovered a new infestation. This is certainly something that needs to be immediately reported and investigated by the state.

On the linked tab, you will see a contacts tab. I would suggest that you go to that tab and call the number listed under Pest Exclusions Branch and report what you know directly to the people who need to know about this. They may already know about the infestation, but then again they may not. And if not, these are the people who will investigate the sites and determine if indeed what you see are JBs. Tell them about every site of which you are aware that may be infested.

The good news is that if there is not a lot of irrigated turf or agricultural land nearby then in your climate, control and then eradication are probably a good possibility, especially if it is caught early and localized.

I am now retired, but worked for Canada's equivalent of the USDA Animal and Plant :Health Inspection Service for more than 35 years. I have worked on a number of exotic pest eradication projects in Canada over the years as a project manager and later on the enforcement side. I know how difficult, costly and frustrating they can be to deal with. But the State of California is very experienced and very good at dealing with this type of issue. Please follow up on this and get the identification issue properly dealt with. You will be doing both yourself and your state a huge service.

Good luck and please be assertive.


Here is a link that might be useful: Japanese Beetle Pest Profile California Dept. Ag..

    Bookmark   August 8, 2014 at 8:07AM
Thank you for reporting this comment. Undo

We have tons of them here in PA this year. We have periodic infestations, and this is one of the years, apparently. I use the beetle traps. OK, maybe they do attract beetles from other areas, but it sure does my heart good to see how many we take out of circulation.

    Bookmark   August 8, 2014 at 8:15AM
Thank you for reporting this comment. Undo

I very much hope yours are not JBs. They cause so much destruction to our crops and flowers for around 10 weeks here every summer. We start out finding a few dozen daily early to mid June each year with the numbers increasing to the hundreds and then thousands daily. Within the past couple of weeks, they are back down to only a few dozen a day and should be completely gone for the year soon. It seems rather late in the year for them to just be starting to appear, so hopefully, itâÂÂs another less problematic bug. HereâÂÂs the best close up I have of mine for comparison:

    Bookmark   August 8, 2014 at 10:28AM
Thank you for reporting this comment. Undo

I found a couple of better pictures of my Japanese beetles. Again, here's hoping yours don't look like this:

    Bookmark   August 8, 2014 at 10:52AM
Thank you for reporting this comment. Undo

You must have been really tired if you saw a black beetle on the page that I linked ;-)
The beetles shown there are shiny metallic green with copper wing covers.
What you describe sounds exactly like a Japanese beetle.
Fairly small, almost pretty.
Rick has provided great info and an excellent link.
I'm sure he's right that you should report the infestation.

    Bookmark   August 8, 2014 at 10:59AM
Thank you for reporting this comment. Undo
hairmetal4ever(Z7 MD)


I'm pretty sure that's where they come from.

    Bookmark   August 8, 2014 at 11:00AM
Thank you for reporting this comment. Undo

hairmetal4ever , I do believe you are right!

    Bookmark   August 8, 2014 at 11:04AM
Thank you for reporting this comment. Undo
jerijen(Zone 10)

Sow What -- I'm wondering if what you have might be fig beetles. Japanese beetles HAVE been seen in SoCal, but not often.

You can see a very good picture of them, at:

They fly, though they are reminiscent of the Goodyear Blimp, and they are very very easy to catch and kill.

They go after figs, but they LOVE tomatoes. And yes, they will also eat rose blooms, particularly loving those with many many petals.


    Bookmark   August 8, 2014 at 7:13PM
Thank you for reporting this comment. Undo
jerijen(Zone 10)

A Suggestion . . . Please look at the link I sent, and get some photos of your beetles, if you can. I'm pretty sure you have fig beetles.

When they show up here, DH gets a wide-mouthed jar, and puts some rubbing alcohol in it. He can easily scoop the beetles out of the air, and the alcohol kills them. We put netting over our tomatoes for this reason, and I would do the same with your fig/kumquat trees.

I've sent a note to Baldo Villegas -- a rosarian who is an entomologist. A very GOOD entomologist. We'll see what he has to say.


    Bookmark   August 8, 2014 at 9:16PM
Thank you for reporting this comment. Undo
jerijen(Zone 10)

OK. Sow What -- I've talked with Baldo. What you need to do is take photos of your beetles. Post them here, or you can send them to me, and I'll send them to him.

Then, you need to call the County Ag Dept., and tell them what you THINK you may have, and ask their advice.

    Bookmark   August 8, 2014 at 10:45PM
Thank you for reporting this comment. Undo
Sow_what? Southern California Inland

Locusts, anyone???

It hasn't been easy making this a priority during this busy work week, but I don't want to see the gardens I created destroyed, not do I want to become the Typhoid Mary of the plant world. So in addition to calls to some of the appropriate agencies, I got help from a master gardener instructor, and there is now a gallon water jug full of green and bronze metallic beetles heading to the big fig tree in the sky. Thank you everyone here who helped shortcut this for me. It's not over, and any additional information and help with ID will be greatly appreciated. Seeing so many of these creatures swarming your fruit trees and roses is not fun.

Jeri, after catching the first one, I made a prelimary ID of Figeater Beetle, so I'm heartened to see that's what you're thinking as well. If those are less damaging than Japanese Beetles, then I hope I never get to experience what JPs can do. Unfortunately, this doesn't look like the "Japanese Beetle" I was shown. That one was smaller, rounder, and the colors were reversed. I only saw a couple of them in that garden, and when we went there today in hopes of catching one, we didn't find any. Is it likely those were really JB? I assumed the brown patches in the turfgrass were from over-irrigation and uneven distribution -- some areas are so muddy I sink. What are some similar-looking possibilities?

Regarding the Figeater Beetles, where did they come from, and what can I expect next? We caught a huge number of them, but not all. The remainder took off for points west, but will they return? There are no figs left; they destroyed the entire crop. But damage to the kumquats and roses was much less, so I assume those are still targets?

If Balso Villegas is able to help sort this out I'll be very grateful. I do have pictures (too tired to post tonight), and the MG instructor will take one in for positive ID.

    Bookmark   August 9, 2014 at 5:04AM
Thank you for reporting this comment. Undo
rhizo_1 (North AL) zone 7

Should be easy to figure this out....Japanese beetles and the green fruit beetle (fig eater) don't look alike at all. Sow_what should be able to quickly Google images of both and decide which beetle he has.

    Bookmark   August 9, 2014 at 5:44AM
Thank you for reporting this comment. Undo

Google-ing isn't even necessary, just have a look at the link that rideauroselad provided earlier

Here is a link that might be useful: rideauroselad's link to CA Dept of Food and Agriculture

    Bookmark   August 9, 2014 at 8:46AM
Thank you for reporting this comment. Undo
jerijen(Zone 10)

Baldo says, it is imperative that you contact the Dept. of Agriculture for your County IMMEDIATELY.

There is every probability that this is NOT Japanese Beetles -- BUT there is a chance that it IS. And if it is, the County must be made aware.

Please don't delay. Contact them ASAP. Then, we will ALL know for sure.

It is B A L D O V I L L E G A S.

Use his name when you call Ag. They should know that name. (God knows, all of the Ag people in MY County know him.)

He has now retired, but he was for years the State's top Entomologist, and he still consults for them.

    Bookmark   August 9, 2014 at 12:52PM
Thank you for reporting this comment. Undo

Yes, definitely the bug should be shown to the county ag dept. and ID confirmed, so I'm glad to hear the MG is taking one for a positive ID.

At least several times in my career specimens sent to CDFA with tentative IDs as a particular weed or pathogen have turned out to be a) not what it was thought to be though closely related and b) new to CA and therefore not in the manuals. Our ag departments have some fantastic people with ID abilities that are global, as opposed to local, and these days, unfortunately, almost anything might turn up in CA.

    Bookmark   August 9, 2014 at 1:48PM
Thank you for reporting this comment. Undo
Sow_what? Southern California Inland

Jeri,running like crazy today. Can you please ask B aldo if he'll call me at number on Humpty Dumpty House website. Thanks. Jannike

    Bookmark   August 9, 2014 at 5:55PM
Thank you for reporting this comment. Undo
hoovb zone 9 sunset 23

more likely the arizona fig beetle, Cotinis mutabilis

Here is a link that might be useful: Cotinis mutabilis

    Bookmark   August 10, 2014 at 4:54PM
Thank you for reporting this comment. Undo
jerijen(Zone 10)

hoovb -- Yes. I agree with you ... because Fig Beetles are pretty common in SoCal -- whereas, Japanese Beetles would be rather startling. It's just "more likely".

That is, btw, why our tomato plants are covered with netting (though we have not yet seen any of the beetles here).

    Bookmark   August 10, 2014 at 5:00PM
Thank you for reporting this comment. Undo
Kippy(SoCal zone 10. Sunset Zone 24)

Those are ugly!

knock on wood, but thank goodness I do not recall ever seeing one here.

    Bookmark   August 10, 2014 at 10:42PM
Thank you for reporting this comment. Undo
Sow_what? Southern California Inland

Tom, at the Dept of Agriculture was very helpful. We think the original, which I was told was a "Japanese Beetle" was actually a Bear Beetle. Dept of Ag will be putting out traps in the adjacent field just in case. He thinks there's at least a small possibility one JB may have come in on a plant, so we're not taking any chances.

BTW, he did say there is a JB outbreak in Sacramento presently, so let's hope they get that under control quickly.


    Bookmark   August 11, 2014 at 5:02PM
Thank you for reporting this comment. Undo
anitasacramento(z9/14 CA)

Yes, some JBs were spotted in Sacramento in an outlying community, Carmichael. I'm hoping they don't head downtown toward my garden and the cemetery, and that they are contained quickly and thoroughly.

    Bookmark   August 14, 2014 at 12:13AM
Sign Up to comment
More Discussions
Where are they now? (Francis Dubreuil & other MIA roses)
The previous threads on this topic (and a few others)...
For those of us in drought-stricken areas of California,...
Tessiess, SoCal Inland, 9b, 1272' elev
Proliferated roses and the fashion runway
Lots of fashions featuring red (HT) roses by Dolce...
about the David Austin bagged root roses out there now
Over on the rose forum there was a report of Austin...
Duchesse de Brabant: Evaluation and Photos
Accidentally put this on the "Roses Forum"...
Sow_what? Southern California Inland
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™