Bad Beetle Karma

I realized after my interview last weekend that I had never actually covered Japanese Beetle Bags on my blog!  That omission must be remedied!

I’m sure you’ve seen them–they are for sale all over.   The sad truth is that they don’t work.

Sure, they fill up the bag-o’-death in a really satisfying way, but they also attract many, many more beetles into the area that don’t get caught.  As long ago as 1985, there was pretty clear evidence that putting the bags out actually made the damage from the beetles worse.

Beetle bags contain a combination of lures–the bright yellow color mimics flowers, there’s a feeding attractant, and also a female sex pheromone.  It is the buggy equivalent of a giant flashing neon sign advertizing a message equivalent to “FREE SEX ORGY AND ALL YOU CAN EAT BBQ WINGS + BEER”.

A lot of beetles come to the trap–but less than 25% of the beetles attracted actually go into it.



Here, look at the data.

That’s from a 2009 study that looked at the specific behavior of beetles attracted to the trap.  They concluded that it’s not a problem with trap design; it’s a problem with beetle brains.  Scarabs are notoriously poor fliers; a few will probably bean you at top speed if you stand around outside long enough in the summer.

Their braking strategy is about the same as the one I use on rollerblades–find a large object, smash into it, and hang on.

So, Japanese beetles fly into the area where the trap is and most of them miss it.  They hang around the trap–because they know that orgy must be around here somewhere–and eventually hook up and start eating. Outside the trap.

Some of them do eventually find their way into the bag later on, but the total catch is still pretty dismal.   And you just paid money to bring all these pest insects into your yard. Oops.

One recommendation that’s commonly made, since the traps do work, just not the way we want, is to buy them and give them to the neighbor you hate the most.  Then their garden will be gobbled up, and your beetles will all fly over there.

Sounds great, right? Except. Here is where the Karma comes in.

One of the reasons these beetles are so evil is they have a 1-2 punch.  No only do they eat your fruit and veg, they lay their eggs in your yard. And eat your grass from the roots.

So, if you send all your beetles over to your neighbor’s yard with the traps…they will lay thousands of eggs over there. And even more beetles will come right back when the grubs emerge from his/her yard.  Payback is a bitch.

So how can you control them? Honestly, I have had the best success with a Mason jar full of soapy water. Find a small kid and tell them you’ll give them a penny for each beetle in the jar. Problem solved.

You might also enjoy this video about Japanese Beetle Control created by the University of Maine.  Ayup!


Switzer, P., Enstrom, P., & Schoenick, C. (2009). Behavioral Explanations Underlying the Lack of Trap Effectiveness for Small-Scale Management of Japanese Beetles (Coleoptera: Scarabaeidae) Journal of Economic Entomology, 102 (3), 934-940 DOI: 10.1603/029.102.0311
Gordon, F. C., & D. A. Potter (1985). Efficiency of Japanese beetle (Coleoptera: Scarabaeidae) traps in reducing defoliation of plants in the urban landscape and effect on larval density in turf. J. Econ. Entomology, 78, 774-778

Wired, Pheromones, and Conspiracies

Wired has a very nice article on the controversy over the use of LBAM pheromone in an urban area in California, in which they do an excellent job balancing both science and public reaction. From Wired:

“Since material safety data sheets can make even the most benign molecules sound terrifically dangerous, vigilant citizens will express their concern about rather innocuous substances — damaging their credibility with the scientists who should listen to their objections — and making it hard to sort out any real threats.”

Rather predictably, the comments have a high level of burning stupid:

“All of you posts supporting the collusion and concentration of power by a wealthy few big ag/chem corporations better get informed or stop writing without revealing your ties to these corporations. IT IS NOT A PHEROMONE, it is synthetic in hugely, hugely unnatural concentrations with lots of carcinogenic and mutagenic inerts. The spray is inhaled deep into lungs like silica and asbestos. We got sick. Animals died. Some of us are still sick. Has one person been contacted who filed a pesticide related health complaint? – NO! Isn’t that enough for you doubters? Don’t you respect the people,or do you just respect and believe the CDFA/USDA, who are nothing more than propaganda machines for big corporate interests.”

I really just don’t get the conspiracy thing.

I have a lot of friends that work for USDA, and they are just some of the nicest folks around. This is also true of friends that work for agrochemical companies. None of these people would go along with a massive plan to cause harm or defraud the public.

This is also true of the people I worked with when I was employed by a pharmaceutical company, the other “big corporate interest” that gets a lot of blame. They all worked at that company because they believed they could truly create change with their work, and make lives better.

Are companies profit motivated? Sure.
But nearly every big company that has behaved badly has been brought down by an insider. You might be able to get a few people corrupt enough to misbehave, but they will be found out. (To get an entire corporation to lie, it apparently takes a Vice President.)

The other thing I hear a lot is that the USDA, college faculty, and state employees are getting rich by working with the agrochemical industry.

Uh. No.

Sure, we take money from companies, in the form of grants and contracts. And you would not believe what a pain in the ass grants and contracts are. Right now, if I buy a centrifuge using the money from Grant A, I am not supposed to use it for work on Grant B. Every dime is strictly accounted for. In a rather crazy, counterproductive way, actually.

You can do some consulting work, but the total amount of time you spend on different projects is tracked. If you try to dip into too many pots, you will get a phone call that you won’t enjoy.
This is not a lucrative job. I’m not poor, but I’m not rolling in dough and shilling for agrochemicals either.

I have almost 20 years of experience, I am in a senior leadership role at a large research station, and I have never made more than $55,000/yr in my entire life.  Comfortable, yes. Rich, no.

Being a scientist, especially an agricultural scientist, is not a fast track to riches and fame.

But I digress.
Back to the article.

I liked these comments:

“This pheromone has to be labeled as a “pesticide” simply because the end result of using it is the destruction of a pest. If water is sprayed and used to destroy a pest, then it too will have to be labeled a pesticide.”

“What would you suggest? I like to ask this of people who whine and criticize, because they never have the answer. Think on it for a while, and when you come up with the solution to the problems that span 6,000,000 square miles and encompass 300,000,000 people, by all means, let us know what it is.”

Related posts: