Used Motor Oil To Discourage Carpenter Bees
As some higher quality paints and stains get close to $100 a gallon, and carpenter bees doing expensive damage, why not try used motor oil? I did an experiment on a small shed, and no bees at least the first summer. Is it any worse than oil products you would buy? Seems like it might be better for the environment to not have to drive somewhere and earn $100 to buy something and then drive somewhere else to get rid of my used motor oil than to just stay home and use what I already have. Not to mention, if it works long term, the time and money savings on replacing trim up on a ladder. When all the variables and pros and cons are added up, what, in the end, is better for the environment?
Edit and Photo: I rarely see carpenter bees attack siding. In my case I am proposing testing the used motor oil ONLY on the underside rake and eave overhangs and their fascia’s (where most bees drill). I am concerned about rain washing anything harmful off the fascia’s but not underneath. The way I detail my drip edge should prevent a good bit of rain from contacting the wood, but with wind, it is a concern of mine. What you see is used motor oil on rafter tails, roof sheathing boards, and fascia. Water based stain on vertical board siding (battons not up yet).
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Used motor oil can contain heavy metals and other toxins. That's why it needs to be disposed of properly. They will leach into the soil and potentially the ground water in that use case.
Some states, including Florida, classify used motor oil as a hazardous waste.
Thank you. What evidence do you have to support that used motor oil is worse than oil based paints or stains on the market? And if it is a provable degree more harmful, when considering all the other variables including the few I listed, which way is better for the environment, and by how much?
I was very careful when I coated the underside soffet area. Honestly I think 10-15 drops of oil fell to the ground. If you think about the average human and how many drops of oil that hit the ground to get us around or to feed us, 10-15 is not much. The benefit of protecting a building and the contents might be a worthwile trade off.
Laws are often silly and do not reflect math or science, the two great bullshit detectors...
mikemcp,
I'm a bit confused. If you have already decided the answer to your question, why are you asking?
I did not expect that response from you Malcolm. I have always respected your expertise and advice. I am not sure what I have said that would make you think my ideas and questions are not worthy of answering. I was actually hoping you would comment with some thoughtful insight. What makes you think I have the answer? Why would I ask a bunch of questions if I had the answer?
You know, if a person cant come here of all places and get an answer like I am asking, why bother with any of this. The cliques of some of you on this site, with your snide, elitist attitudes, building houses for the rich.... Man...FTW
mikesmcp,
AC200 gave you his take, which you completely dismissed. Based on that it seemed to me you already had a settled opinion on the subject. Both your replies read like you have a chip on your shoulder. Maybe some other posters will have better luck replying.
A settled opinion? I have a theory. I thought I might ask here for more anecdotal evidence and maybe be pointed to some scientific studies, or a discussion. Sorry my way of speaking rubs you wrong, but I dont see what you mean after I re read what I said. I very much do have a chip on my shoulder because of interactions like this one. You say I completely dismissed AO200, well you might want to re read my response. I mean its right there. I do completely dismiss laws that are based on made up lies, like religion, fasle science, etc., but I dont think I completely dismissed AC200. I asked for evidence...
I get the picture, Im not welcome here. No problem, I dont like the person you or your buddies are either. Good Bye.
Environmental aspects aside, what evidence is there that this is a good treatment regimen for the problem at hand? (Note: I don't mean anecdotes.)
Well, anecdotes are what gave me the idea, and I posted the questions because when I search online, it is mostly two opinions, neither offering evidence. One crowd say dont do it, its bad, there is a huge difference between used motor oil and oil based paint, the law and the epa say so. The other crowd has been using it as an effective wood preservative for ever, thats how we always done it. Both those ideologies dont help me much. I did find a peer reviewed study that claimed used motor oil was even more effective then clean motor oil to deter termites. Nothing on bees yet and I am trying to find that article again. I posted these questions as a way of enlisting help from smarter people than me with a science back grounds to go a little deeper than the drivel you find on a google search for the most part. Bees are not termites, but I theorized it might work, so I experimented. I would appreciate it, if people on here would re read my questions and logically address them, rather than what the comments are reflecting so far.
https://www.ffps.org.ng/journal/2010/vol_3/resistance_of_engine_oil_treated_wood_against_termite_attack.pdf
We can have a logical scientific discussion on the topic. There is a huge difference between oil based paints and used motor as a wood protectant. Oil in paint (or water for water based) is the carrier solvent for the paint solids or preservatives for the wood. Used motor oil contain metals and contaminates that are spread on the wood. Rain can wash these off and into the ground.
Many, many years ago when I was a practicing and licensed Chemical Engineer, I managed the hazardous waste program for a large utility. All of the used oil from vehicles, heavy equipment, machines and turbines was collected for recycling. It had to be filtered, cleaned and tested to be reused as base stock or used as fuel in refineries and such with controlled emissions. A use case as you described would never be considered.
Here is a very basic page from the EPA on handling of used oil from households.
https://www.epa.gov/recycle/managing-reusing-and-recycling-used-oil
Does oil based product you buy protect wood better than used motor oil? I dont have a study to cite but I do remember reading one about it being effective in detering termites. I can probably find it when I have more time.
I am under the impression that oil products you buy do contain metals, am I wrong about that?
You say my use case would never be considered, but you can find thousands of cases online where people claim it has been working great as a wood protectant for decades. I dont care who is right or wrong, but I am not taking anyones word for it. I need evidence, and I suggest everyone consider taking that attitude before that movie Idiocracy becomes a documentary...
Also, see my edit on original post. About my concern for rain washing harmful thigs into the ground. As a chemical engineer, I am very curious on what you can say about what harmful metals or contaminants get washed off of store bought products compared to my used motor oil?
There are lots of things that work well until they are identified as environmental health and or environmental hazards. Lead in gasoline, paint and solder, asbestos, PCBs in transformers and paint to name a few.
You seem to have your mind made up, but I certainly would not agree that applying used motor oil is more environmentally friendly than using a commercial paint.
Because you and the gubment say so, got it. Thanks for the "logical scientific discussion". I wont bother any of you again.
You offer no logical scientific evidence or engage in any reasonable discussion, just trolling. I gave you an answer based on my formal education and experience like many of the pros do here. And you are wrong in many things that you say. Good luck with your oil.
I have a carpenter bee problem and it's frustrating as hell. They're near impossible to get rid of. One method that seemed to work was taking one of those basement bug foggers, turning it on and putting the nozzle in a few of their holes. You see it come out of the other ones. Very satisfying. You have to move quick, because those foggers don't last very long. The last time I did it I used a few cans. Of course, then they moved to another location....
Since they hibernate in there over the winter, I think it might've treated the nests and limited the hatching in the spring, or whatever they do. I hate the buggers, but I'd never put engine oil on or around my house.
Ok, but what is in those foggers that might be harmful. I have no evidence that my used oil is any worse...
Ok, you would never put it on or around your house, but you use the foggers? You trust the foggers and fear the used oil, did I interpret that right? I am asking how you came to these conclusions?
Hey I just remembered something. Spring 2023, before I coated with the used motor oil, I found one single 3/8 hole started on backside of my eave fascia board. I had been considering this, but right away I coated the crap out of that area. A few days later I coated the rest. So, the bees did not move to a different spot in this example. I agree though, if you plug a hole with wood putty or caulk, they just move to another spot or many times re open their hole. Signing off for a while, trying to corral you guys back to my original questions, or at least close to the nature of my questions is exhausting.
We're dealing with a pesticide with these foggers. They are used in basements and closed areas to deal with bugs. You're not supposed to hang around while these foggers are going off or inhale the vapors. Clearly harmful short term but not long term. If they were, they'd be outlawed. So yes, I trust the foggers and fear the used oil.
But the small amount you're using probably won't hurt anything. I just wouldn't want it on my house. Where I live, they test the soil surrounding below ground fuel oil tanks for seepage and 'pollution' if/when you go try to sell your house. God help you and your wallet if they find anything.
It's the kiss of death to have fuel or engine oil in your house soil. So yes, I fear the used oil.
Mikesmcp,
If you can read this, used motor oil is highly flammable as it contains some amount of unburned gasoline due to incomplete combustion. Thats nasty stuff to coat your house in even if it repels wood bees, and when it rains the runoff will ruin your siding, windows, patios and landscape, its going to be a mess that gets tracked indoors and is toxic to people and pets.
In my backyard tests, used motoroil coated white pine did not seem any more flammable than plain rough cut pine. Have you ever painted a board with used motor oil, had a control board un painted, and played aroud with a torch? You can get each to burn if you hold it on long enough, but I did not see much difference in the time it took. Maybe you can see a flaw I didnt in my test?
I was unclear about what I was coating so I edited my original post. I am concerned about rain washing off the fascia, but not concerned about the underside of the overhangs. BTW that used motor oil soaks in and the rough cut takes a lot of it. After it dries, the surface is no longer that oily.
And again, one of my original questions that has not yet been addressed, how much worse is it than an oil based product you buy?
>And again, one of my original questions that has not yet been addressed, how much worse is it than an oil based product you buy?
Do you get that oil-based paint is nothing like motor oil, the only similarity is that both contain the word "oil" in their names?
The major environmental risks from oil based paint are the carrier solvents evaporating and causing air pollution and even a localized hazard in confined areas; and contamination of groundwater if wet paint gets into the soil. Once the paint is dry the residue that remains is pretty inert, it's kind of the whole idea with paint that it doesn't dissolve or evaporate.
Motor oil doesn't dry like paint. It's not highly evaporative, and what doesn't evaporate isn't inert. It presents a serious risk of groundwater contamination. Used motor oil also contains all sorts of combustion byproducts, many of which are carcinogens, which is why used motor oil is classified as hazardous waste. In the United States, disposing of it in the way you suggest would be a violation of federal law.
Regardless of its efficacy against carpenter bees it's not something I would be slopping around the outside of my house.
You should read the whole thing dude.
Mike,
I think you need to find an answer to your question elsewhere, it's unlikely anyone on GBA has expertise in the field that you seek information.
Aside from being repetitive, you seem eager to agitate the people who have taken time to respond to you. The answer you seek is irrelevant to me, the world and probably yourself, acting as an outlier for the sake of being stubborn simply put is sheer folly.
"answers"
mikesmcp,
As Martin, one of my snide, elitist buddies used to occasionally say about posters: You are advice-resistant. Just put the oil on and stop wasting everyone's time.
irrelevant
Mike,
Here's perhaps an alternate perspective - I suspect you grew up in an area similar to myself where using creosote was common, as was used oil, diesel, ATF, and everything else that came out of a motor. For others too - in case this practice seems like a one off. It was very common practice at one time.
Just so were all on the same page - it used to be common practice to prevent rot on barns, shed, fence posts, and any other exposed wood, to apply a coating of some type of "junk" petroleum based product as a paint. I quote junk, because nobody in their right mind would have bought new motor oil to coat their barn with. They would have looked at you like you're crazy. However, on basically any farm operation there's a glut of lubrication and maintenance that happens. Hydraulic oil, diesel engine oil, gear oil, etc. that accumulates. At the same time, everything was made from wood. What was a person expected to do with all the byproduct?
Here's where maybe my adjacent perspective comes in. Much of the lumber used wasn't treated, as it was often sawn locally from whatever wood was there. Untreated wood doesn't last long, especially Maples, Pines, and Poplars that were common around my region. However, those woods soaked in the used oil *did* last a long time. My grandfather (Born 1924) was the one who first taught me about the three R's (reduce, reuse, recycle), and reusing is really what this whole comment is about.
Assuming you've got a glut of used oil that has already been paid for, and can be used to extend the life of a maintenance item, in an operation that is essentially a family affair. What would a reasonable expectation of that person be? It would be to reuse what you have, which greatly lowers the man hours required in an operation, re-uses what you have on hand, and at the same time makes the disposal problem less of an issue.
This prevented the waste from being dumped directly in the ground, as it was too valuable just to throw away, in a sense. It reduced the number of trees being cut down, and made it possible to get other jobs done. I assure you that it would have otherwise been dumped directly into the ground if it had not been deemed valuable for other purposes.
Now to the real point of my comment -
In the era when this was common, in my region, interstates where two hours drive away, there was no internet, no big box stores, practically nothing commercially available like we enjoy now. People used what they had and it worked. They weren't stupid by any means, but they were ignorant to many of the adverse effects of everything around them. They died of cancer, black lung, heart disease, dementia, and everything else you could think of too.
What was perhaps the least amount of bad that could be done at one time, we might even grace as the best practice, compared to the alternative of dumping it directly into the dirt. The difference is that now we know more about what the effects of using oil in this way are, and at the same time, have an entire catalogue of products that are better suited to the job at hand. Used engine oil doesn't polymerize and harden (cross link) in the same way that linseed oil, varnish, paints, and other products do. That's why you'll see it fade over time. It's constantly distributing itself deeper into the wood. That's nice from the pure insect resistance standpoint, but not from the rot / groundwater effect standpoint. If you want to keep it up, it'll need re-coating with used oil, periodically now. It's not a treatment that lasts forever, regardless of what the lore tells you. I've seen it fade and wear off and still be eaten. Then, at the end of life, the structure either gets demolished (or burnt in the old days), or buried, and that oil eventually finds its way back in to the ground or atmosphere as CO2. So while the pollution may have been delayed, at the end of the day it was still as bad as pouring it straight into the soil, or burning it for heat.
So to answer you question, will used engine oil deter carpenter bees? Yes. Will the small amount of oil that diffuses from the wood into the ground (at demolition, I know you said you're only using it in the rafter tail area) in your scenario likely have a devastating impact to the environment at large? Doubtful, because you're likely one of the handful of people left using oil as paint, and likely on city water that undergoes treatment before it reaches your house. The additional fire risk is almost negligible, since the whole things made of wood anyways. However, if this practice hadn't stopped, it would have been a problem, as *everyone* was doing it.
Now that you've got the library of Alexandria at your fingertips, you can try to do better with the information you have. There are better ways do accomplish what you were trying to do, without the side effects. There are countless insecticides that you can browse on domyown that are indicated for carpenter bees. Property management goes a long way too.
The reason you're getting a lot of push back is because others are (rightly so) encouraging you to explore alternatives, even after the fact that you've applied it, and (puts on parent hat) you're being stubborn about it. We're not here to scold new ideas, but the idea isn't new, and it has run its course, and been obsoleted. What would have been better for the environment *today*, would have been to bottle that up, take it to your nearest big box car store, and recycle it the next time you go to buy new oil. What you did may have been better for the environment 50 years ago.