tomc
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A posse of Japanese beetles

Usually when these appear in pestilential amounts, it is on the upper new growth. Yesterdays visitation was in the usual place but only on the upper bloom of rosa rugosa. Nothing else 'upper' was so stricken.

I shook off a fist full and took them to the sidewalk where I stomped them.

It was most satisfactory... ;)

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applestar
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:twisted: :lol:

imafan26
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I'm glad we don't have Japanese beetles. Don't send any either. I have enough trouble with Chinese rose beetles.

I plant my roses near the street light and I have four o'clocks planted nearby. It keeps them at bay. I don't have any beetle damage to the roses in the front yard, just the Mr. Lincoln in the back yard.

tomc
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My fiendish Japanese beetles were either doing something X-rated or gorging on the blooms or my rugosa's.

They won't kill the plant, I'm not sure they will even set back hip production. I still don't likes 'em though.

tomc
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My fiendish Japanese beetles were either doing something X-rated or gorging on the blooms of my rugosa's.

They won't kill the plant, I'm not sure they will even set back hip production. I still don't likes 'em though.

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applestar
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In my garden, they are making lace out of runner beans at top of trellis where I can't reach, hazel leaves, cherry leaves, and new raspberry shoots.

But they seem to have arrived later than in the last couple of years.

Ohio Tiller
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I had to break down and use sevn on the potatoes because of them this year apparently they like real hard cold winters!

Mhasan
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These Japanese beetles are really upsetting me. This is my first year of landscaping - I only had a few baskets last year and didn't notice them. My neighbor said they were around last year too. I've killed at least a hundred in the last week by picking them off and dropping them in soapy water. Is that a lot? We seem to have an infestation in our neighbourhood. I walked on the street next to me and several of the trees had hundreds of them. I've read that the traps attract more than they catch. On the weekend I must have gone out at least 10 times and picked them off my New Guinea impatiens baskets, pansys in baskets, geraniums in baskets. The rest of the flowers are in the ground, such as roses, hibiscus plant. They are devouring my peach tree leaves. And mating on them - it's disgusting. And some are on the pear tree and I'm worried about the rest of my flowers. I can't be out there all day picking them off ! My neighbours have the beetles too. I went to a nursery and they said there is no spray for them. However I think there might be some sprays in the US. Are there any sprays that work in Canada?

All our hard work to maintain the trees, roses and other flowers is going down the drain. If it's not disease, then it's pests. It's really hard to fight mother nature. Also I've seen a couple of mice running through my flower bed. Gross! Very upset about both issues. What can I do??

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rainbowgardener
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Something is out of balance to have an infestation like that. Getting it back in balance may be a couple year project. For right now hand picking is a good solution. If you come out very early in the morning while it cool, they are slowed down and it is easier. Rest assured you won't have to do it much longer. They are really only adult beetles above ground for about a month. They are mating now, pretty soon they will lay their eggs in the soil, usually in lawns, and then the adults go off somewhere and die.

After awhile the eggs in the soil hatch in to larvae/ white grubs. After they are grubs, you can treat the lawn with milky spore disease and beneficial nematodes (NemaSeek). These are available on-line or in garden stores. They will kill the grubs in the soil, without attacking anything else. Late August or early Sept would be the time to do it and then again in spring before they turn into adults and emerge.

That should reduce your problem with JB's, but definitely not eliminate it, because the adults fly so they can come in to your yard from else where.

Things you can do now to deal with the adults include spraying the leaves of the plants they are infesting with Neem oil. It is not a poison and does not kill on contact. The beetles take it in when they are eating leaves and it works inside them as a hormone disrupter eventually preventing them from eating/mating. But it will take a few days or a week to know it is working. It is said they hate garlic, so you could make a garlic spray or better a garlic oil spray (if you find garlic oil, it is much more concentrated). This won't kill them, but it should help repel them away from your plants.

For the future, along with treating the lawn grubs, it helps to jump on the hand picking immediately when they start emerging (usually in June). When the adults start feeding, they put out a chemical signal to alert all their friends that this is a good place, so they attract more and more. Birds are good predators on them, so it helps to have bird feeders and bird baths in your garden. Besides, who doesn't love birds in the garden? It is even possible that the mice are there because the JB's are there and the mice are eating the beetles.

You can also grow trap crops for them, best is grapevine or wild grapevine. I have wild grapevine that grows as a weed, but I always leave some. Especially when it is flowering, the JB's love it and congregate there. That makes it easy to dispose of them when they are gathered, but after awhile I decided I didn't need to because they were staying on the grapevine and not bothering anything else.

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applestar
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Great advice. We all seem to have them, but Milky Spore or. Nematodes is definitely the way to interrupt their lifecycle and reduce future generations/infestations.

..but when you say "hand picking" are you literally hand picking?

Especially huge infestation on things like hanging baskets, long branche tops, etc. I find it easier to toss a big bag over the plant, shake the plant to get them off and into the bottom of bag, then close the bag and stomp on it very thoroughly -- humming the Mexican Hat Dance tune or La Cucaracha if you want to do this exactly like me :>

I also hold a large container of soapy water (usually a 1 gallon pail) and shake them in. A lot of them will fly off, but I don't worry about that. Sometimes, when I'm short of time or patience, I'll just shake the plants or lightly beat them off with a switch to simply get them off and disrupt them.). At least some of them will end up in the bag or the soapy water eventually.

...generally a good idea to wear a hat while doing these though I admit to not always following my own advice. But I have short hair and de-bugging my hair is not that difficult,

Mhasan
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Applestar and Rainbow Gardner: Thank you both for your suggestions. I will give the Neem Oil a try. Yes, I am literally handpicking them with surgical gloves and dropping them into soapy water. My trees are not that tall yet, and I guess on the baskets I am getting the ones on the lower flowers/leaves. I know they are only around for 4-6 weeks, but they are still a big pain. I do plan on getting a service to do the grub control. I'm doing by best, but as I said, we seem to have an infestation in the neighborhood so they are coming from neighboring yards and trees. One neighbor said there were more last year - I can't believe it ! Can't wait until they're gone. O:)

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applestar
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Things might be different in Canada, but be sure of what the "service" uses or it may turn out to be some toxic chemical.

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applestar
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I have been looking a little more into the Japanese beetle predators and other natural controls because they are out of control this year in my garden -- They are absolutely all over my pole beans. Not only turning the leaves into lacework, but feasting on the blossoms. I'm finding them piled on top of each other three high (somebeetle in the stack is obviously confused :P )

I really suspect that somebody in the neighborhood is hanging those pheromone traps and attracting them.

I'm not REALLY worried for the beans because I'm harvesting more than we can eat inspite of whatever damage they are inflicting. And I'm sure these populations didn't come from my garden because when I was digging around this spring, I hardly saw ANY grubs. We're talking maybe 2-3 grubs in a 10 ft x10 ft area. Which I think should mean that even if all of these three-stacked beetles try to lay eggs, whatever in the soil that has been keeping them down would continue to do so. I've a fairly diverse Ground Patrol in place -- I've spread milky spore in the past, I have ground beetles, I have moles, I have birds. I have considered spreading predatory nematodes but have not. But I'm confident there are at least *some* resident population.

Still, I wanted to find out if there are any other JB predators that I didn't know about. And casting around the 'net, I came across this excellent article. It actually debunks milky spore, which was a surprise to me, but has additional information that was very informative. I'm particularly hopeful that this year's massive JB invasion would trigger the predatory tiphiid wasps that are mentioned to be present in this area to come and enjoy the banquet.

Japanese Beetle:
The Continuing Struggle to Achieve Successful Biological Control

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applestar
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A brief excerpt about the tiphiid wasps from a linked article:
These two tiphiid wasps are among several natural enemies imported for the biological control ofJapanese beetle. Tiphia popilliavora is native to Japan, where it attacks the larvae of the Japanese beetle (Popillia japonica), as well as to Korea and North China. In its native areas of Korea and North China, T. vernalis is parasitic mainly on scarab species in the genus Popillia other than Japanese beetle. T. popilliavora was the first of the imported parasites to be released. Fewer than 100 adult wasps from Japan were first released in New Jersey in 1921-22, but they quickly established and their progeny and strains from Korea and China were distributed over the infested areas of 10 states by the end of 1950.

... T. vernalis was first released in New Jersey in 1925, and by 1953 over 2,000 colonies of this species were distributed over 15 states.

...The adults are 1/4" long shiny black wasps. The adults of T. vernalis emerge during May and early June and feed on aphid honeydew.

...The biology of T. popilliavora is similar to T. vernalis, but the adults emerge in August and early September and feed on nectar from the blossoms of umbelliferous plants, especially wild carrot, rather than honeydew.

...Under favorable conditions, T. vernalis can parasitize up to 60% of beetle larvae in an area and T. popilliavora somewhat less. The abundance of both species is greatly influenced by the availability of adult food sources. The females feed in the morning and then fly relatively short distances to deposit their eggs. This is why parasitism by both species tends to be greatest in grassy areas near weedy borders that contain aphids or wild carrot.
https://www.entomology.wisc.edu/mbcn/kyf508.html

...I'm cautiously optimistic that my garden conditions could match the "favorable conditions" mentioned in the article. I get aphids-a-plenty in spring, and for the fall Tiphia, I have (not wild but) regular carrots blooming right now, and as luck would have it, I have been deadheading them since I'm not interested in saving carrot seeds this year since Certain *someone* gave me a HUGE stash of seeds. :() This has meant that they have been continuing to bloom. Also have celery and other umbelliferous bloomers that are blooming now and will be blooming later. 8)

One concern I do have is that I had the impression that Japanese beetles came late this year. That may mean the T. vernalis missed them altogether, and the T.popilliavora may not find the 3rd instar grubs they are looking for. :|

...on the other hand, I did recently see several severed JB heads on leaves of plats under the beans (a squash leaf in this case) I thought birds or praying mantis, but maybe it was T. vernalis larva at work. :twisted:

ETA -- ah. I have it wrong. The wasps actually sting the grubs in the soil.
After mating, female wasps burrow into the soil and search for grubs.
https://www.hort.uconn.edu/ipm/turf/htms ... Tiphia.pdf
https://ipm.uconn.edu/documents/raw2/The ... hp?aid=167
This one has photos and descriptions that I recognize, so I think I do have the spring Tiphia in my Garden/Ground Patrol :-()

Mhasan
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I haven't tried the traps as I've heard mixed reviews. They are devouring my mom's Rose of Sharon like crazy ! Now that they have exhausted my neighbour's trees, JBs are enjoying my beautiful hibiscus leaves. I thought JBs should have been gone by now?

So I'm going to use a lawn service and they will apply the nematodes, probably in September. I'm also planning to alert all my neighbours on neighbouring streets and recommend that they get nematodes as well.

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applestar
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Sound like an excellent plan! Hope that will work for you. :D

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rainbowgardener
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If they came later, then their life cycle will be done a bit later, but, yes, when the adults emerge, I think they only live for about 6 wks or so, mate, lay eggs in the soil and die.

Mhasan
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Yes, I think they came later this year. Thanks.

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applestar
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I saw a bunch of small black wasps on the carrot flowers today -- I didn't have my phone with me to take pics so can't be sure if they were the fall tiphias or some other black wasps.... 8)

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DDMcKenna
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Thank you, just got done reading that. That sure explains a lot. I think I remember them when I was a kid up there. I think it's too hot for them here. But we still have our share of bugs.

I really appreciate you providing the link

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applestar
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You are welcome. I'm learning a lot from there too.

The other Garden Patrol parasite of Japanese Beetles, also introduced, is a Tachinid fly:
I. aldrichi overwinters in a puparium within the body of the dead host in the soil. The adult flies appear from mid-June to mid-July in New Jersey and feed on aphid honeydew and nectar. The females attach an egg on the thorax of newly emerged beetles. Each female can deposit up to 100 eggs over a 2 week period. The egg hatches in 24 hours and the maggot burrows into the body cavity of the beetle to feed internally. The larvae kill the beetles in about 5-6 days (compared to the 4-6 week life span of a non-parasitized adult), during which time the beetles bury themselves in the ground.
https://www.entomology.wisc.edu/mbcn/land508.html#land2

...it's too late in the season now, but I'm going to look for JBs with eggs on their heads next early summer! :twisted:
Photos of Japanese Beetles that have been oviposited with eggs of Istocheta aldrichi - Winsome Fly - BugGuide.Net
:arrow: https://bugguide.net/node/view/85196

:idea: ...ha... Looking at the photos again, strictly speaking, the eggs are not on their heads but on their thoraxes (middle segment between head and abdomen) as described in the article.

Mhasan
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I saw some new bugs on my pansies - they look a bit orange-black. Could these be the wasps?
They don't look like typical wasps.
Will try to get a picture.

tomc
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Japan beetles don't try very hard to escape, which is a good thing. they did top and eat out one bloom or rugosa rose, before moving on to pole beans.

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rainbowgardener
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I liked the article! Particularly this: Birds such as grackles, meadowlarks, starlings, cardinals, and catbirds have been reported as significant predators of JB adults. In addition, pheasants, chickens, ducks, geese, and guineas readily feed on the beetles

I don't have poultry, but grackles, starlings, cardinals and catbirds are in my yard.

Also note the adult tachnid fly feeds on honeydew from aphids. Another good reason not to try to eliminate all the aphids. Besides the tachnids, I'm starting to think the honeydew is an important element in the food chain, lots of bees and wasps like it.

Mhasan
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Hi, I'm still waiting for the Japanese beetles to leave. They don't seem to be ending. I'm still drowning 20 - 30 per day. And these are just the ones I caught ! :evil: Now they've moved on from the peach tree leaves to the fruit. :(

Can you remind me which are the trap plants I should get and when to plant them?

Thanks.

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rainbowgardener
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I doubt trying to plant a trap plant now will do you much good for this season, but you could start now to get a jump on next year. I think grape vine or wild grape vine is the best trap crop for them, but four o'clocks , larkspur, castor bean, borage, marigolds, light colored zinnias are also reputed to be good trap crops for them. Note that several of those are toxic plants, not so good if you have a dog or toddler that eats plants.

Encouraging birds to your garden is also a good thing for pest control generally.

Mhasan
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Thanks - I have zinnias that finally bloomed, but the Japanese beetles prefer my red roses. I've got marigolds too, yellow and orange, but haven't seen any beetles on them. They seem to go for the tall flowers - my red rose is 4-5 feet high and my scarlett hisbiscus is about 4 feet. My mom offered me her Rose of Sharon and I am glad I did not take it. All the Rose of Sharon trees in my neighbourhood are heavily infested with Japanese Beetles.

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RogueRose
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Thankfully I haven't had any in my garden ::knock on wood:: but when I go riding my horse in "the wilds" (as wild as NJ can get) they are devastating a lot of vegetation. It's real sad to see how they are completely eating everything....although a lot of is russian olive which can go away. :) Oh and also - it sucks when you have big curly hair and they get CAUGHT IN YOUR HAIR!!!!

valley
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Could it be that some kind person is picking them off plants into a paper cup and driving them away from their property to release them where they will be safe?

I wonder how the chickens would like them.

Richard

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Lindsaylew82
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4 o'clocks really help! They like to eat them a lot, but they don't get very far because they're toxic!

Mhasan
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OK, let's say I plant 4 o'clocks. Will they stay off my other flowers, or will I just be attracting more Japanese beetles to my frontyard and backyard?

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Lindsaylew82
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They prefer them to roses and sunflowers, all I can tell you. They eat it and the die.



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