by Connie Oswald Stofko
Buffalo-area gardeners are familiar with the Japanese beetle. These bugs are pretty, but so damaging to our gardens.
As you might guess from the name, Japanese beetles come from Japan, where they’re not much of a nuisance because their natural enemies keep them in check.
In our area, grubs damage lawns by feeding on grass roots. The adult beetles attack the foliage, flowers or fruits of more than 300 different ornamental and agricultural plants.
Unfortunately, Japanese beetles are here to stay in the Buffalo area, and the best you can do is to manage them (we share some suggestions below).
However, you can make a big contribution to our environment by making sure you don’t spread Japanese beetles or other invasive pests to areas that are currently free of the invaders.
August has been proclaimed “Invasive Plant Pest and Disease Awareness Month” by the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS). Gardeners can do their part to battle invasive pests.
Prevent the spread of invasive species
APHIS says the best way to fight invasive pests and plant diseases is by preventing their spread.
Japanese beetles were first found in the United States in 1916 near Riverton, New Jersey. Since then Japanese beetles have spread throughout most states east of the Mississippi River.
The APHIS has a Japanese Beetle Quarantine in place to help contain the spread of Japanese beetles. Because Japanese beetles can hitch a ride on airplanes, planes from eastern states are inspected for the bug when they land in Arizona, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah and Washington.
Japanese beetles are just one example of invasive species that cause trouble for gardeners and farmers.
You can help prevent the spread of pests and plant diseases — both from your garden and to your garden– through some simple steps:
- Buy only certified, pest-free nursery stock.
- Don’t move firewood. Many pests can be found in recently killed plant material including firewood. By deciding not to move firewood on your next camping trip, you might just save a forest that could have been ravaged by any number of pests riding on logs to an uninfested area. Keep that in mind when buying firewood for your home fireplace, too.
- When traveling to other countries, declare all food, live animals, and plant or animal products on your return to the United States. Invasive organisms can easily be transported on living plants or fresh products such as fruit. Certain foods can’t be brought into the country because they might harbor pests and plant diseases that could be dangerous to our local plants.
You can learn more about preventing the spread of invasive species with this sheet that includes special tips for gardeners, hikers, hunters and other groups. You can also get useful tips by following the APHIS Twitter feed.
Managing Japanese beetles in the Buffalo area
A good overall guide is Managing the Japanese Beetle: A Homeowner’s Handbook from the U. S. Department of Agriculture. It includes information on traps, chemical pesticides and biological or organic pesticides. It also includes the best and worst plants for your garden when dealing with Japanese beetles, which I haven’t seen elsewhere.
When my garden was attacked by Japanese beetles, I got a trap (one of those bags you hang in your yard), and it filled up fast. The bags may pull some beetles away from your plants, but they also attract beetles from other yards to your yard.
One guy I talked to said he bought the bags as Christmas presents for all of his neighbors to hang in their yards. (Hah! Genius!)
While the trap in my yard may have helped, I decided I needed to do more. I considered chemical pesticides, but instead I went with milky spore, which is a powder that you apply to your lawn to kill the grubs.
Milky spore is a bacterium that’s harmful to Japanese beetles grubs, but not to humans or pets. You have to use it for a couple years until it inoculates the area, and milky spore may be more expensive initially than chemical pesticides. However, once the bacterium is established, it can last 15 to 20 years, so I think you’re saving money in the long run.
You can apply it anytime the ground isn’t frozen. Zehr’s has some good information on milky spore.
I’m in the second year of using milky spore, and I seem to have fewer Japanese beetles.
To get rid of the adult beetles that I do see, I wear those rubbery silicone gardening gloves and crush the bugs as I pick them off the plant.
I’m not sure I understand your question. Are you asking whether the plant four o’clocks are poisonous?
Can You Tell me what is “Yellow” or “four o clock” poisen? Barb
Anne,
Not only is crushing a slow process, it might be counterproductive? Oh, no! I’ll definitely try the soapy water.
I love the idea of using flowers to do our dirty work. Four o’clocks are very pretty. That might be worth a try.
Thanks so much for sharing your tips!
Penny,
Wow! What a great tip! I had tried dropping Japanese beetles into a container of water, but they seemed to swim. I’ll try adding soap.
Thanks so much for sharing.
I was crushing them too until a friend informed me that a pheremone is released when they are crushed, which attracts more JBs! I haven’t yet researched it – has anyone else heard of this? Just to be safe, I stopped crushing and started knocking them off the plants into the bucket of soapy water. This is effective, but I found that I would have to quit my job and do full time duty to keep them under control this way. I’ve also heard that yellow four o’clocks can help – they are attracted to yellow and the four o’clocks poison them.
Since I garden for hummingbirds I can’t spray anything on the plants that my hummers use for nectar. I have eliminated many of the Japanese beetle attracting plants except for my Monarda. I keep a small bucket of water with a couple of squirts of dish soap and knock the beetles into the soapy container early in the morning while they are still ‘sluggish’. No alcohol needed. They die almost instantly.
Milky Spore is the best way to go for the long haul but until you get them under control in the beginning, the container (large or small it doesn’t matter) of soapy water is the cheapest and safest way to go….remember a little soap and water never hurt your kids or your pets and it works.
What a great tip! Dish soap and alcohol, especially in the quantities that you’re using them, don’t sound as if they’d have long-lasting effects on the environment. I’ll have to give it a try!
Thanks so much for sharing!
I do not use the bags and tried Seven, but we have been using a recipe that we found some where and it works quite well killing the beetles and is not expensive. Unfortunately, we are only killing the beetles not the grubs. The recipe is water, rubbing alcohol and dish soap. I no longer know the exact measurements, but all summer I have been making this potion a few times a week, and I use mostly water with 3-4 squirts of dish soap and about a 1/4 cup of alcohol in a quart squirt bottle a little shake and I squirt the beetles and come back a little while later and see them hanging there dead. Great satisfaction!