Shiny pests return for more

Michael Sears

A Japanese beetle crawls on a flower near S. 43rd St. and Drexel Ave. in Franklin on Tuesday. Wauwatosa was hit with these pests in July and Brookfield is just now encountering them.

You can see them glimmering in gardens, nestled in rose blooms, whether at the Boerner Botanical Gardens or in your own backyard.

It's "the bug from hell," as University of Wisconsin-Madison entomologist Phil Pellitteri calls it.

Japanese beetles have returned with a vengeance.

They attack a wide variety of plants - roses are a favorite - leaving a trail of destruction that includes leaves so full of holes they resemble lace.

This year the population is up, thanks to last year's heavy rainfall. Get used to them, because they will be here until September.

"We really don't have any other kind of insect that has this kind of impact as far as making gardening no fun," Pellitteri said.

The beetle first entered the United States in New Jersey almost a century ago and has been slowly migrating west ever since. Wisconsin is now in the thick of that migration.

This year, Japanese beetles have been attacking the Milwaukee area in waves.

Wauwatosa was hit in July, while Brookfield is just now encountering the pests, said Debbie Pings, a horticulturalist at Hawks Nursery. Across the region, neighborhoods may seem fine one day and be overrun a few days later. How can you tell they've arrived? Look for browned birch or linden trees.

The Japanese beetle is about a half-inch long, with a vivid green body covered by wings that look almost bronze. They hit lawns, gardens and trees every July - give or take a few weeks - and at the end of their season, lay their eggs in lawns. The larvae grow, eat and sleep underground until the following summer.

Sprays and traps

Defending against the beetles is not easy. The most common method is to spray with chemicals. Horticulturalist and gardening expert Melinda Myers suggests homeowners who are just beginning to see the beetles try an organic insecticide made of neem. She says it is most effective when used early.

If neem does not work, there are many synthetic sprays that may be effective, but they carry more risks.

Myers, a regular contributor to the Journal Sentinel's Entrée section, specifically suggested sprays marked for use against Japanese beetles containing the active ingredient imidacloprid. The insecticide is sold under many brand names and for many different purposes, including as a flea killer for pets. She cautioned against using sprays on the rose blooms themselves.

"You don't want to spray the flowers because you kill the bees," she said. Bees are needed to pollinate the plants.

Another problem with sprays is that they must be reapplied at least once every three days, Pellitteri said.

Although they may offer frustrated gardeners the satisfaction of seeing their roses' killer powerlessly struggling in a hot plastic bag, beetle traps may actually do more harm than good. Myers, Pellitteri and Pings agreed that beetle traps, which work by attracting the beetles into a plastic bag with a tapered neck, may actually attract more beetles into your garden in general.

"They get thousands in the trap, but I'm not sure they have thousands in the tree," Myers said.

Pellitteri suggested that only people who live on large tracts of land and can put traps 100 yards away from their flower beds should use them. He said the only significant successes of the traps have been with widespread deployment of traps across a community.

"The traps out there have been scientifically proven to make life worse, not better," Pellitteri said.

A third option is using a systemic insecticide, which is poured at the roots of a target plant and makes the plant material toxic to the beetles. While some people may be concerned by the prospect of drenching their soil in insecticide, Myers said, given the Milwaukee area's dense soil, it may be safer and more controlled than spraying insecticides, which can blow with the wind.

The only problem? You have to use them three weeks before the beetles arrive for the season. Myers suggests homeowners leave a reminder for themselves on their calendars now for June 1, 2012.

One last option: flicking off the beetles by hand into soapy water, especially in the morning, when they are clustered. It's tedious and unpleasant - and might work best in small gardens - but for perspective, Myers said Olbrich Botanical Gardens in Madison does this regularly.

Blame your neighbors

The beetles have a lot of stamina. They fly up to a half mile to find food, so controlling your own garden will not necessarily get rid of them. Pellitteri said golf courses provide the ideal habitat for beetle larvae since they are watered frequently and offer thick grass roots to eat. If, however, you do suspect that your lawn is nurturing beetle larvae, you can wage both chemical and biological warfare against them.

Myers noted a new chemical, Acelepryn, has proved highly effective against Japanese beetle larvae while being safe for other species. However, it is currently only available to professionals, so if you want to treat your lawn with it, you must find a professional service that uses it.

Garden centers also sell various parasites that can be applied to lawns with the hope of snuffing out the larvae. Myers warned, however, that such an effort could take years to be effective.

Although the number of beetles appears to be up, the damage they do may be leveling off. Pellitteri said the beetles have come into balance with the Midwestern ecosystem.

Shirley Walczak, Boerner's director, said the gardens' roses had actually sustained less damage than last year.

"We just try to keep things under control," Walczak said.

Pellitteri said the next pest to watch for is the brown marmorated stink bug, another accidental gift from our friends to the east (in this case, Pennsylvania). The stink bug attacks fruit trees, and in some orchards it has caused a total loss of produce.

"If you're an apple grower, you're really going to have to gear up," he said.

The good news? Pellitteri says it's at least three years before Wisconsin sees significant populations.

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  1. To get rid of the Japaneese beetles, send in the Bolivian tree lizards, then the Chinese Needle Snakes to get rid of the tree lizards, then snake-eating gorillas to get rid of the needle-snakes, and then when wintertime rolls around, the gorillas simply freeze to death. Problem solved.
  2. Thanks for an extremely helpful story. I just wish they were easier to get rid of.
  3. I keep trying to teach them how to swim. Stupid things keep drowning. I'm up to at least 50 a day
  4. well they are in my area as well, south on howard avenue, my roses look horrble. :(
  5. Ugh..these were all over my roses tonight. Bastiges.

    Looks like I will be beetle picking tomorrow morning with a bucket of soapy water.
  6. We spray the rose bushes down with a Dawn dishsoap solution every morning. Doesn't hurt the roses and kills the beetles. We are also lucky enough that we can place a phermone trap far away from the bushes themselves. What the article forgot to mention is the reason why flicking the bugs into a container of soapy water is nessesary. The beetles, when killed by force (smushing
  7. My previous comment got cut off for some reason Continued from my previous post: (smushing or stomping,etc) causes the beetles to release a phermone that attracts more beetles. Don't kill the beetles! It will only make the problem worse. Drowning them in dishsoap is the way to avoid this.
  8. At least these beetles aren't bugs which like to invade homes.

    We have plenty of bug problems in homes here in Wisconsin: bed bugs, fleas, ect.
    Still, at least we haven't been invaded (so far) by the infamous stink bug which has been propagating in the east esp. around Virginia, Maryland and NY, and are gradually and relentlessly moving west.

    These bugs like to invade homes and are extremely resistant to household pesticides. When they are smashed, as with a fly swatter, they give off a strong odor like the inside of old tennis shoes.

    Stink bugs aren't here yet, but they're coming.
  9. Hanging those traps in your yard do indeed attract additional beetles. Big mistake to do that. My father used them for two years after seeing his linden and only one of his birch trees devoured. And only certain types of birch are tasty treats for the beetle. He used the liquid application on the yard and the granular as well. This year his trees look fine. So far. Yes this is an excellent article.
  10. Just noticed them last night north of the city. My pole bean plants are destroyed. Took only one day.

    I don't think we've ever had them before. Last night I eyeballed 50 in just a minute.
  11. Unfortunately when you have a large scale invasion of Japanese beetles the only way to get rid of them en masse without spraying is a trap. My poor linden tree is half eaten this summer. I trap thousands of them a day and drown them in a bucket of soapy water. The good thing is that the wild turkeys love to eat them when they are dead so they don't go to waste.
  12. What? Nobody blaming DNR yet? Nobody claiming they heard helicopters at night dropping the beetles from the sky?
  13. Two weeks ago, I noticed these guys crawling all over my purple plum tree in my back yard. They had done a very fine job of perforating most of the leaves. Not wanting them to completely destroy my nice tree, I bought some insecticide from the home improvement store. I used Spectracide brand's Triazicide (liquid), mixed it in a sprayer per the instructions, and sprayed it all over the tree leaves. Within 20 minutes, so many of these little guys were falling off the tree it sounded like it was raining. The article warns about spraying certain chemicals and the impact on bees....I can't comment on that, but can tell you the Triazicide certainly worked to get these beetles off my plum tree.
  14. Please don't use just any will kill the GOOD insects too!!!!! Use a large bucket...fill with soapy sudsy water...wack the stupid...clustered bugs in the bucket with your other hand...they fall.......flounder... it drowns them...rather quickly.......This is fun...and safe...and costs nothing.......CHEMICALS are not the way to go......please think about the consequences.Thank you...good article.
  15. My neighbor has 3 Japanese beetle bags, and they do work well, you just have to empty them into something like a trash bag and tie the top so they die. I have used sprays and they do work, but I do have concerns about harming bee's. I use a needle nose pliers and pluck then into a soapy bucket or just kill them. Nasty little buggers.
  16. Fortunately, they are only going after one of our many rose bushes. Unfortunately, it's my favorite and most fragrant. Tried the Ortho's Bug Be Gone, but found picking them off in the morning works much better. I fill a sour cream container half full with sudsy water, and cover.
  17. I thought the beatles were from Liverpool? Not Japan.
  18. They have also attacked my tropical hibiscuses.
    Going out with soapy dishwater now. Thanks for the article.
  19. Great article. The beetles are here in Greendale too. They have devoured
    half of my neighbors birch and are starting on my roses and magnolia.
    Headed out with sudsy water in a few min and June 1 is on my calendar
    for next year!
  20. Sevin is very effective on linden trees...I have only had to spray it on once to keep them healthy. Also, consider applying milky spore to your will kill the grubs in successive seasons without chemicals. Kinda pricey, though...
  21. We noticed hundreds of these things on various bushes we have out in Sussex. Never seen them before this year.
  22. Milky Spore is said to work for some. I'd apply that or some sort of grub killer in the fall to kill the overwintering larvae. You need to kill adults and larvae. I guess in Japan they are kept in check by disease and predators. I think there is some sort of wasp that attacks them.

    Sevin works very good on beetles, just be careful when you spray it. Try to spray in the evening or morning when there is no wind. I'm not a huge fan of the newer Neonicotinoids. They are very toxic to bees and are SYSTEMATIC. They are actually absorbed by the plant. Neem may work, but you are too late now. I've read where you need to spray it BEFORE the beetles arrive, so when they land on the leaves, they get a yucky taste and move on. Another option is SurroundWP. Its a clay product that is used by organic fruit growers. It works very well on Japanese beetles, but does turn your plants white and sticks to everything you get it on.

    Here on the north end of La Crosse, I've seen very few. Probably killed 20 total in the last month. They seem to prefer my sweet cherries and raspberries.
  23. Although expensive to do properly, I've had very good luck with Milky Spore. About 5 of my neighbors and I have applied it the requisite 3 times and the beetles have definitely gone down in number -- those my wife finds, she drowns in soapy water. (We're just north of Indianapolis and have been battling these bugs for years.) I too recommend staying away from heavy chems because the impacts go far beyond just japanese beetles and can harm everything from bees to praying mantises to butterflies.
  24. I've seen a ton of these (they kinda look like the emerald ash borer) but haven't seen our ladybug counterpart that much this summer. Just wondering when these are going to arrive as well.

    CG realist actually had the solution correct in the first post. Classic!!
  25. The traps will work well. They will attract every beetle within a mile radius to your yard - DO NOT USE the traps!

    Bayer makes a systemic that you pour on the roots of your ornamentals in May (cherry, birtch, etc) that gets absorbed by the roots and into the leaf system. It is very effective but too late to apply now. You need to do it a month before they arrive.