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lanette1982

Unusual behaviour of japanese beetles

Lanette1982
9 years ago

I am new to this website. Sometimes, I find good info. I decided to post this online because maybe, some of you experienced similar problem with infestation. I contacted a couple of entomologists but some of them were unable to help me; and I am still waiting for response from other professionals. I do NOT want to kill any birds or other mammals and beneficial insects. Timing is significant to me. So, your recommendation and/or experience will be highly appreciated.

On 06/28/2014, approx. at 12 p.m., I've noticed a lot of Japanese beetles on my blue spruce. My blue spruce is small, approx. 4 feet.

The strange thing is: Japanese beetles were only on the Western side of blue spruce; they were mating and did not pay any attention to me. So, I took Sevin spray (freshly made; contains carbaryl), and sprayed directly on JB. They did not stop to mate, so I sprayed 3 times and they still were mating. So, I easily pick them up and put in a basket with soapy water (Notice: JB did NOT fly away and it was easy to collect them; it was looking like JB were "glued" to the Western side of blue spruce. ). Notice: they feed/ mate from 12 p.m. to 3.30 p.m. on my apple trees and spruce.

I checked blue spruce, and I did not find any traps for JB. We also NEVER placed any traps/baits for JB and I do NOT want to place them. I read that JB are attracted to sweet smells such as roses, and other flowers. Our plants are rhodies, pines, spruces, yews, azaleas, boxwood, and junipers because we have highly acidic soil. We do NOT have any flowers in our garden. However, we have 2 apple trees (I changed soil PH only around apple trees, boxwood, and junipers). Both apple trees are severely attacked by Japanese beetles (from top to bottom and all sides; I used Sevin on apple trees in the evening but it does not help too much). I got an opinion, that JB eat leaves on apple trees, and after that they are flying to mate only on Western part of blue spruce. Notice: apple trees are growing in different bed than blue spruce. I did NOT see JB on any pine, junipers, or rhodies.

I hope I am wrong but it looks like someone sprayed our blue spruce with pheromone that attracts JB, and that spray was pretty expensive. So, it was sprayed only on Western part of spruce.

So, if JB are attracted by sweet smell of flowers and female sex pheromone then I should use a different smell which can dissolve/remove sex pheromone.

I was thinking to smash garlic, onion, cayenne pepper and mix with water but I am not sure that it will be effective. Neem oil has bad smell but neem oil will change needles from blue to green (I am 100% confident about it).

If it is not too too difficult for you, could you, please, answer these questions:

1. What chemical pheromone can attract JB (e.g. liquid, powder form...)?

2. What chemical or organic way to dissolve/remove that pheromone?

I know even if I will remove Blue spruce then someone can spray that JB pheromone on a different tree or bush. In addition, I like my spruce and I do not want to kill it or put in a trash.

Well, I took "Environmental Science" class. Once, our professor asked question in class, " What would we do if we got dangerous hazardous material in mail?"

I answered that I would mail it back because I did not order it; some students told that they would contact Extension service and recycle it; some students said that they would put it in the yard of neighbors.

Comments (4)

  • jean001a
    9 years ago
    last modified: 9 years ago

    I think you are stressing yourself by over-thinking, then proposing an illogical theory.

    Slow down and deal with the beasts where they are.
    Pesticides didn't work. So if it's a reasonable task, collect them & dump into soapy water.

    To collect them easily, use a variation on the beat-sheet technique:
    Spread a sheet under a portion of the tree, then knock the branches with a broom handle.
    Gather up the corners of the sheet and dump groggy mating captives into bucket of soapy water.

    See Using a beat sheet at the link below.

    Here is a link that might be useful: Using a beat sheet

  • Lanette1982
    Original Author
    9 years ago
    last modified: 9 years ago

    It is IMPOSSIBLE to collect all JB using a beat sheet or dumping into soapy water. If someone placed JB trap on the border with your yard and wind blows towards your garden, then Japanese beetle can be on your yard. JB can fly as far as 2 miles. So, what goes around comes around.
    Here is link
    http://insects.about.com/od/insectpests/f/japanese-beetle-traps.htm
    According to my research, "You want the beetles to leave your yard, not come flying in by the thousands. You are better served by a Japanese beetle trap if you present it to your neighbors as a gift. Let them hang it in their backyard, so your beetles move to their garden. Or, you've got to hold a neighborhood meeting and convince everyone to hang beetle traps, to stop the migration from yard to yard."

    Some insecticides/pesticides work on JB and oriental beetles. I've noticed dead oriental and Japanese beetles around my blue spruce after I used Sevin. However, Sevin can kill beneficial insects as well. Therefore, I want only RATIONAL and EFFICIENT response. Personally, I believe my own eyes, facts, research, and recommendations of professional or experienced people. I operate by logic NOT by emotions.

  • ApacheRosePea00
    9 years ago
    last modified: 9 years ago

    Do you suspect a specific person that may have sprayed your spruce? And why? Otherwise, I find it hard to believe that someone would go out of his or her way to attract a known difficult critter to someone else's space.

    I would think that rational thinking might suggest diseased plants and thus, the beetles having a field day first? Or a food source near the spruce if they are not harming it?

  • art33
    9 years ago
    last modified: 9 years ago

    Hi Lanette and welcome to GardenWeb!

    Regarding the beetles being mostly on the western side of your blue spruce, from my experience the beetles tend to congregate on the sunny (warmest) side of bushes and trees. For example, I have a crepe myrtle bush in my back yard that only gets afternoon sun. I seldom see any Japanese beetles on that bush until it starts getting sun, and then ninety percent of them will be on the sunniest (warmest) side. If the western side of your blue spruce gets the most sun, that could explain why the beetles are on that side.

    I use “Safer Insect Killing Soap” on Japanese beetles, it seems to work very well. I use the concentrated stuff (5 tablespoon per gallon of water) in my lawn and garden sprayer. The product is biodegradable and considered environmentally safe. It only kills bugs that you spray it directly on.

    Hope this is helpful,

    Art

    This post was edited by art33 on Tue, Jul 1, 14 at 0:12