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  1. #101
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    Doctor woodrock, FWIW upon moderate exposure to PO on bare skin I will get an occasional tingling or itching sensation but will not develop any of the usual manifestations of PO; rash, blisters etc. So perhaps urushiol or some other other component of the sap is directly responsible for innervation. I'm not sure what the vapor pressure of urushiol is but when working in really dense PO there is a distinct odor which accompanies a slight burning sensation to my eyes. Urushiol or some other component?
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  2. #102
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    Quote Originally Posted by Moe Ped View Post
    It's "Doctor woodrock" from now on.
    There are more questions than answers at this point, so if there really is a doctor in the house, it would be nice if she can step in to help explain things.

    We haven't gotten to the initial immune response yet, but I would like to summarize that I'm confused on a lot of things that I wrote above, so, what I'd like to ask is that people who know, explain some of the open questions.

    A fundamental open question is what's the composition of the oleoresinous sap? If we knew the composition, we could better target the surfactant and a preventive (e.g., we'd understand how the activated bentonite in ivy-block works, for example). What's the percentage of urushiol in sap anyway? What's the best way to wash the sap away? These are open questions because I don't have a clue what the chemical composition of the sap is.

    I have emperical experience, but what I'm asking in this post is theoretical experience.

    For example on the chemistry, why does washing our clothes "oxidize" the urushiol, such that our clothes immediately turn black where exposed? And why isn't that oxidized urushiol infectious? Why doesn't the oxidized urushiol penetrate the skin and elicit a reaction?

    Why does it seem that my gloves are black with oxidized urushiol, but I never washed them in the washing machine? I just left them in my glove drawer. And that don't seem to be infectious.

    Another example on the theoretical chemistry where I'm confused about is what "properties" should I expect the catechol and quinone to have. If I knew how the catechol behaved, I could better undertand how to target it for example. Does it behave as an oil? A phenol? The catechol is obviously aromatic, and aklyl at the same time, and it's polar, but does it have properties of an alchol? What surfactants or solvents would a chemist expect to work on this molecule.

    Another question is how it can be that, emperically, I find that washing with surfactant hours later, seems to work in the real world, when all the immunology discussions seem to indicate that fifteen minutes is all that you have before the urushiol tunnels under the upper layers of your skin?

    Another open question is what exactly is the nature of the process by which the sap penetrates the skin? Is it pure osmosis past membranes? Or does the sap simply wick in between cells as it seems to be doing in the diagram in a prior post?

    An open question is what on earth is doing the oxidizing of the urushiol catechol to the quinone? Is it a cell doing the oxidation? Or an enzyme? What?

    Another open question is why the itching? Sure, there's damage, that's for sure. But what exactly is causing the nerve cells to fire a response? Are they touch (aka pressure) receptors? Are the nerves themselves damaged? Do they somehow sense the detritus and debris of destruction?

    My hope is that someone on this forum has knowledge or ideas that may help all of us answer those fundamental questions, because, fundamentally, I don't understand this process well enough to explain it correctly, nor how to deal with it correctly, if I don't know the answers to those basic questions.

  3. #103
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    Quote Originally Posted by Moe Ped View Post
    FWIW upon moderate exposure to PO on bare skin I will get an occasional tingling or itching sensation but will not develop any of the usual manifestations of PO; rash, blisters etc.
    That's interesting.

    Do you get that itch right away (in the first day?) or later (after a few days)?
    Most people only get the itch way later, like two days later, right?

    Whenever they get the itch, I agree that something is making the nerves fire. But what?
    Pressure?
    Damage?
    Exudate?

    Quote Originally Posted by Moe Ped View Post
    So perhaps urushiol or some other other component of the sap is directly responsible for innervation.
    Maybe. Certainly some things (e.g., fiberglass, nettles, a fresh haircut) cause itching relatively quickly.

    Nothing I've read says that there is any manifestation of getting the sap on your skin that is "mechanical" or "chemical" though. But it could be so.

    The whole itch thing is strange as it's the major PITA of poison oak.

    I think we've all experienced a poison oak rash where it felt "good" (so to speak) to burn our arms in the hot shower, just so that we could feel relief afterward. What is going on there? Are we using up potassium ions? Are we simply changing the sensation we interpret in our brains?

    That we have little logical explanation for the itch is bothersome to me.

    Quote Originally Posted by Moe Ped View Post
    I'm not sure what the vapor pressure of urushiol is but when working in really dense PO there is a distinct odor which accompanies a slight burning sensation to my eyes. Urushiol or some other component?
    You have a good point that the volatility of the sap (and of the aromatic urushiol) may play a role somehow.

    Interesting. I don't "smell" poison oak, and I've had sap literally ooze onto my gloves from a chainsaw cut of wrist-thick vines, but my wife can smell stuff I never smell, so I know my sense of smell stinks.

    We don't know the composition of the sap yet, so, the smell that you smell could be esters or pheromones (or whatever) in the sap. Maybe it's a simple sap or maybe it's a complex sap. I don't know what the heck is in that sap but I can certainly imagine that there is "stuff" in the sap that you can smell.

    Of course, the sap isn't generally exposed to the air unless the plant is bruised, but if you're out riding in it, then it's bruised.

  4. #104
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    Quote Originally Posted by woodrock View Post

    Do you get that itch right away (in the first day?) or later (after a few days)?
    Most people only get the itch way later, like two days later, right?
    Within an hour; gradually goes away or when I wash up.

    If I get a quantity of raw sap on my skin or get scratched by a PO branch to where it breaks the skin I will get what looks more like a chemical burn that will scab but I don't get a wide-spread rash.

    Another anecdotal tidbit is when I used to ride my moto headlong through PO thickets the PO juice would cause pits in the gel-coat of my helmet. I don't have a clue why this would occur; I just took it to be an omen as to how nasty the substances in the sap were.
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  5. #105
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    Quote Originally Posted by Moe Ped View Post
    Within an hour; gradually goes away or when I wash up.
    Interesting.

    Maybe it's irritating your skin somehow so it's important for us to figure out what the chemical composition of the sap is, other than just the urushiol (which could be in tiny percentages or large percentages for all I know).

    Quote Originally Posted by Moe Ped View Post
    If I get a quantity of raw sap on my skin
    I don't remember ever getting a visible liquid drop of the sap on my skin, although, like everyone who chain saws it, I can see the clear sap oozing out just a minute or two after slicing the thicker stuff.

    And, of course, I've been slapped in the face a billion times, but, I never tried dripping a liquid drop on my skin.

    Maybe I should test that out?

    Quote Originally Posted by Moe Ped View Post
    or get scratched by a PO branch to where it breaks the skin I will get what looks more like a chemical burn that will scab but I don't get a wide-spread rash.
    You and someone else bring up a good point which I had never thought about until this thread, which is how the reaction can differ if the sap gets in a cut versus when it's just lying on the skin surface.

    It could be the same reaction, or, since the mechanics are different, it could be a different reaction. I need to research that more so your observations are important since I don't remember ever getting the sap inside a cut, although, like everyone who works outside, I have plenty of cuts, so, if it happened, I just didn't remember it.

    I'll research that if I can. Thanks for the idea to flesh out the (never ending) book!

    Quote Originally Posted by Moe Ped View Post
    Another anecdotal tidbit is when I used to ride my moto headlong through PO thickets the PO juice would cause pits in the gel-coat of my helmet. I don't have a clue why this would occur; I just took it to be an omen as to how nasty the substances in the sap were.
    Pits in the gel coat.
    That's another very interesting observation.
    Thank you for the idea.

    I don't know what the gel coat is made up of, but my kids are grown up, so I can grab one of their old helmets and cut a vine and drip the sap onto a marked spot, and test it out.

    Do the pits happen relatively soon? Or must I wait a long while?

    The sap is "probably" a sugary substance so what is causing the pits isn't likely the sugar. The urushiol is a benzene ring with two hydroxyl groups and an alkyl group, so chemically, I would suspect the benzene ring causing the pits more so than the OH or alkyl groups.

    I guess I could test a benzene-like solvent on the helmets also.
    This is California, where all the good solvents are gone and what's left don't even say what is in the can (surprisingly) last I checked at Ace Hardware when I went looking for xylene.

    So I'll have to look to see what solvents are benzene-like that I can buy at a California hardware store to test another spot on the helmets.

    Any idea what the gel coat is made of?

  6. #106
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    Quote Originally Posted by woodrock View Post
    Pits in the gel coat.
    That's another very interesting observation.
    Thank you for the idea.

    I don't know what the gel coat is made up of, but my kids are grown up, so I can grab one of their old helmets and cut a vine and drip the sap onto a marked spot, and test it out.

    Do the pits happen relatively soon? Or must I wait a long while?
    This would have been in the late 60's so my guess is that the gel coat was probably polyester resin. They were Bell brand helmets. Seems like the pits would show up after a couple of weeks and may have been exposed to water during that time (riding in the rain); they were distinctly black. (Obvious in the only color then available; white) Almost like the pigment was floating away being replaced by the common PO black. Not very deep but easily felt by running fingers over them. Haven't noticed this occurring in modern helmets (but my riding style has changed too).
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  7. #107
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    Quote Originally Posted by Moe Ped View Post
    This would have been in the late 60's so my guess is that the gel coat was probably polyester resin. They were Bell brand helmets. Seems like the pits would show up after a couple of weeks and may have been exposed to water during that time (riding in the rain); they were distinctly black. (Obvious in the only color then available; white) Almost like the pigment was floating away being replaced by the common PO black. Not very deep but easily felt by running fingers over them. Haven't noticed this occurring in modern helmets (but my riding style has changed too).
    technically, there should have been a coat of paint on the helmet. glossy enamel stuff, not sure specifically what Bell woulda been using at that time, but most likely something enamel thinned with toluene or the like. gel-coat is (as you correctly state) a thin polyester resin that would get applied to the mold prior to the fiberglass being laminated into place, and it serves to make the outer surface of the helmet smoother and less pinhole-y. it can be used as a finish, but is generally painted over.

    sorry for the tangent. please, keep on with the poison oak lesson. this is good stuff!
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  8. #108
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    Quote Originally Posted by MtotheF View Post
    technically, there should have been a coat of paint on the helmet
    Thanks for the information from you and Moe-Ped about the helmets.
    What Moe-Ped said makes sense in the fact that the urushiol is an aromatic, so, it could easily be a solvent, and, we know it oxidizes black (that's where it got its name from), so, what he says checks out.

    I'm still working on finding the composition of the sap, and particularly the concentration of urushiol in the sap.

    Also, I had promised a writeup of how the first exposure goes since that all-important first exposure sets the stage for all others.

    Before starting that, I should point out a mistake I made in one of the prior posts when I said that the aklyl chain doesn't seem to have an effect on the immune reaction. Apparently it does have an effect, so, scratch that one statement from the prior record, but, I'm working on what that effect is since it doesn't change anything else that was said.

    The first exposure happens in two separate phases, but here is a quickie off the cuff description of the phase that starts with you touching poison oak for the first time (but you don't get the rash).

    As before, the sap gets on your skin while you're just a kid, going out in the woods for your first time. That benzene in the urushiol dissolves fats (lipids) on your skin and the lipids between cells, and makes it down through the first two layers of your epidermis (which itself is the first layer of skin).

    At some point, magic occurs that I'm not sure of how, and chemicals are sent out alerting the Langerhans cells that the urushiol is in town.

    As before, the urushiol is oxidized (again by magic at the moment, as far as I can figure out) to the quinone, and that's when the quinone binds to the surface of a Langerhans cell which starts to digest the quinone.

    In that third layer of the epidermis and at lymph nodes, white blood cells meet up with the Langerhans cell and quinone assemblage but the T cell at this point doesn't recognize the antigen assembly as an enemy. When the langerhans cell digests the quinone, the T cell finally has a complement for the digested stuff, which causes the T cell to recognize the hapten, for the first time, as an enemy.

    [Note: How that t cell got that complement is a discussion for a later post.]

    That t-cell which recognized the hapten starts multiplying like crazy, to the point that there are enough of them in about a week or two weeks, where you're, for the first time, "sensitized".

    For the rest of your life, these sensitized T-cell clones of that first t-cell will roam your body through and through, looking for the langerhans cell presenting a quinone to it (as we described earlier).

    Next we have to discuss how the T-cell got it's complement for the bound quinone, and that's where the major dose of randomness is going to be found, since the body randomly does stuff so that it can defend against stuff it has never seen before.

  9. #109
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    HOT SHOWER
    Yes, once I get the rash (for me that can be 1-4 days later after exposure, it seems), I take a very hot shower every 12 hours, blasting those itchy areas. It feels good!, and I do this for however many days the itching lasts (7-10 days?). This technique Numbs the itching for many hours. After this, I can feel OK all day at work. Then, repeat: after another hot shower session, itching is mellowed so I can sleep all night.
    Last edited by primordial; 2 Weeks Ago at 10:07 AM. Reason: Make it clearer

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    I always imagined the itching is caused by the histamine release and resulting inflammation response (swelling) of the epithelial cells which are highly innervated. When the inflammation swelling cycle stops the itching seems to greatly be reduced and then one gets a slightly different itching such as when a scab is healing. This is likely the result of the scared and dead tissue being exfoliated. No science here just observation.

    Factoid, Japanese lacquer (dark brown bowls, trays and other woodwork) is from a type of tree. Some people are sensitized by handling these articles and the woodworkers who handle the stuff often have to stop the trade. I worked with a wood carver in Japan who had this issue...hence wood carver in the end.

    Other factoid, if you are sensitized to PO, the outside skin of mango has the same or similar chemistry. Years ago, my face broke out like a clown and I traced it back to the mango I had eaten a day earlier. I quartered it and ate it off the skin. Now I slice it off and had not had a problem since.

    Lastely, there can be a pivotal shift whereby the outbreak becomes systemic and not just at point of contact. Very allergic people seem to get it everywhere, but it is more about a full on out of control response vs just contact dermatitis.

    Lastly, I had a doctor tell me once that while this dermatitis is a classic release of histamine and yet anti histamines do not seem to help. Odd, but take it for what ever this is worth.

    One more note, Prednisone steroids works wonders but cautiously recommended. The potential negative side affects and contradictions are far worse the the disease getting treated....far worse. I would say just not worth it. Some of the negative autoimmune responses are downright scary such as destruction of cartilage. Anyway...Google it and see. A buddy had a hip replace when 30 years old...thought to be a result of Prednisone.

    And did you know there is a old wives tail (could be true) that local Indians used to chew on the PO stalks in order to become desensitized. The contradicts the current thought that it gets worst over time. For me, I am less sensitive now vs when I was a kid.

  11. #111
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    Quote Originally Posted by primordial View Post
    HOT SHOWERYes, once I get the rash (for me that can be 1-4 days later after exposure, it seems),
    Thanks for that observation because, it seems that I also take more time than most articles say it takes to develop the rash. For me, it's like for you, which is more than one day almost always, and often more than two, and sometimes more than three days later.

    The main thing, I think, is that this is cellular stuff (no antibodies are involved) so they have to literally "move" around to get work done, which takes time (apparently).

    Quote Originally Posted by primordial View Post
    I take a very hot shower every 12 hours, for however many days the itching lasts (10 days?). This technique Numbs the itching. After this, I Feel OK all day at work.
    I wonder if the heat causes the body to "use up" something it needs to feel pain?
    For example, since nerves fire using electrolytes and neurotransmitters, they might "use them up" (but I'm just making a wild-assed unsubstantiated guess).

    If they did, then maybe, I wonder, the nerves can "get tired" from the shower heat?

  12. #112
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    Quote Originally Posted by Tommybees View Post
    I always imagined the itching is caused by the histamine release and resulting inflammation response (swelling) of the epithelial cells which are highly innervated.
    You bring up a GREAT point which I completely skipped, which is that there are tons of chemicals that are released during a type IV cell-mediated immune response. I always forget about them, so I'll write up what they do in a later post.

    What you're saying makes a lot of sense, in that the histamine that is released (plus the cytokines) themselves, might "irritate" the nerve, either by the physical changes they cause (e.g., making vessels leakier) or by a direct action on the nerves.

    Certainly something is causing the nerves to fire, even though the immune response isn't aimed at the nerves themselves.

    Quote Originally Posted by Tommybees View Post
    When the inflammation swelling cycle stops the itching seems to greatly be reduced and then one gets a slightly different itching such as when a scab is healing. This is likely the result of the scared and dead tissue being exfoliated. No science here just observation.
    Interesting. I kind of agree with you, but I never thought about it before so I'm working on "itch memory". Certainly different things happen at different stages, where healing is later and damage is occurring earlier.

    Quote Originally Posted by Tommybees View Post
    Factoid, Japanese lacquer (dark brown bowls, trays and other woodwork) is from a type of tree. Some people are sensitized by handling these articles and the woodworkers who handle the stuff often have to stop the trade. I worked with a wood carver in Japan who had this issue...hence wood carver in the end.
    Thanks for that story, as it makes sense that the urushiol, unless inactivated, would still be active.
    I would think though, that the "black" part of the laquer means that it's oxidized.
    As you can see from my photo of pressing the black-oxidized cut stem from a year or two ago against my forearm, I wasn't too worried about the black oxidized urushiol.

    Of course, who is to say that there isn't some non-black non-oxidized urushiol in the mix!

    Quote Originally Posted by Tommybees View Post
    Other factoid, if you are sensitized to PO, the outside skin of mango has the same or similar chemistry. Years ago, my face broke out like a clown and I traced it back to the mango I had eaten a day earlier. I quartered it and ate it off the skin. Now I slice it off and had not had a problem since.
    Thanks for that advice. There are a few plants that have urushiol in them. Some say, I'm told, that it's an anti-fungal and anti-bacterial defense mechanism. Dunno if that's why but pistachios, mangoes, ginkgos, cashews, rengas, poison oak, poison sumac, poison ivy, and a bunch of others evolved to contain urushiol in their resinous sap for some reason.

    I have heard people complain that they got poison oak or ivy the first time, but since that's impossible, I think what they had was a previous exposure (sort of like how we get a blood transfusion reaction on our first transfusion due to prior mimicking exposures to bacteria end products that mimic the blood types - although that mechanism requires antibodies whereas poison oak doesn't).

    Quote Originally Posted by Tommybees View Post
    Lastely, there can be a pivotal shift whereby the outbreak becomes systemic and not just at point of contact. Very allergic people seem to get it everywhere, but it is more about a full on out of control response vs just contact dermatitis.
    I'm not sure what you're trying to say, but I think what you're saying is that at some point, the poison oak reaction seems to far outweigh the infection in both size and scope in very sensitive individuals.

    It's a good question of how far the cells migrate. If they can migrate, for example one foot, that means they can cause a reaction in a lymph node on the shoulder even if only the elbow was involved. So it's a good question as to how far these cells migrate, since we know the reaction seems to center around the langerhans cell presentation of the bound quinone.

    Does anyone know how FAR an "infected" langerhan's cell can migrate?

    Quote Originally Posted by Tommybees View Post
    Lastly, I had a doctor tell me once that while this dermatitis is a classic release of histamine and yet anti histamines do not seem to help. Odd, but take it for what ever this is worth.
    You are completely correct that histamine is involved, which I completely omitted in my descriptions (so I need to go back and flesh that out better).

    It's interesting that you have heard that anti-histamines don't help. That's odd. It's probably true, but to you and me, that seems odd. I'll need to dig at that to figure out how that can be.

    Quote Originally Posted by Tommybees View Post
    One more note, Prednisone steroids works wonders but cautiously recommended. The potential negative side affects and contradictions are far worse the the disease getting treated....far worse. I would say just not worth it. Some of the negative autoimmune responses are downright scary such as destruction of cartilage. Anyway...Google it and see. A buddy had a hip replace when 30 years old...thought to be a result of Prednisone.
    I haven't studied the pharmacology yet, so, I'm out of my league on how the steroids "chill out" the immune response. But what you're saying makes sense, as there are always the risk of side effects when you introduce steroids into the body

    I only had prednisone prescribed once, when I had gotten stuck on the mountain overnight, where the moon didn't come out until 4am, so I bedded down, sans any sleeping equipment after a furtive attempt to make it out in the dark.

    Turns out I had bedded down in a lush carpet of the stuff, so, I went to the MD who prescribed the steroid. She told me to take it as soon as possible, before the reaction started, and I didn't get the rash as badly as I should have, given the circumstances, so, I am a believer in the stuff (but I would rather slather on the lather than pop little white pills).

    Quote Originally Posted by Tommybees View Post
    And did you know there is a old wives tail (could be true) that local Indians used to chew on the PO stalks in order to become desensitized. The contradicts the current thought that it gets worst over time. For me, I am less sensitive now vs when I was a kid.
    While I've heard the rumors that Native Americans didn't get it (and that they baked food in the leaves, and made baskets out of the shoots), I haven't found anything scientific that proved they didn't get it.

    Separately, I've read that humans are about the same in susceptibility, overall (although black skin is apparently slightly less affected, but only slightly, according to what I've read).

    I tend to believe that this is something easily tested so, I'm going to have to believe the statistics that say we're all in the same boat, immunologically.

    Certainly Native Americans were "in tune" with their environment, so, maybe they just knew what they were doing better than did we white-skinned tenderfoot invaders.

    Or, since we haven't gotten yet to the concept of "self/not-self" in the thymus (which is why t-cells have a "T" in their name), maybe the Native Americans grew up so close to the poison oak when their immune system was developing, that the shape of the urushiol molecule was considered self in the developing thymus?

    If that's the case, maybe Native Americans a few hundreds years ago were constantly exposed when their immune systems were developing, hence the shape of the urushiol hapten would be considered "self" when it had to pass the self/non-self test in the thymus, causing the randomly developing T cells to be destroyed in the thymus, since they would have passed the "self" test.

    If that guess is anywhere true, it's gonna be hard to prove because I suspect Native Americans today sleep indoors in soft beds just like we do, hence they're not growing up in the woods, so to speak, anymore. They're growing up just like we are at this point, so that theory will remain untested unless someone has a spare baby whom we can swaddle in a poison oak crib for the first year of life so that we can test out that theory in the real world.

    Later I will write up how the thymus self/non-self test is the crucial piece in this "random" madness that determines whether we're sensitive or not sensitive to poison oak.

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    It's going to be a rough year for folks that get p.o. I usually ride one of my favorite trails in SC solo because it's pretty much impossible to avoid. Tahoe Matt followed me down it in early Feb. and, even though it hadn't even leafed out yet, he still got a few patches.

    My g/f manages it with Dawn-infused paper towels immediately post-ride, then a Dawn scrubdown in the shower.

    I saw a video last year of a guy back East that had studied poison ivy and did lots of trailwork involving it. He showed himself handling it, so it seemed to work for him.

    Found it: https://youtu.be/4oyoDRHpQK0
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    Quote Originally Posted by Moe Ped View Post
    This would have been in the late 60's so my guess is that the gel coat was probably polyester resin. They were Bell brand helmets. Seems like the pits would show up after a couple of weeks and may have been exposed to water during that time (riding in the rain); they were distinctly black. (Obvious in the only color then available; white) Almost like the pigment was floating away being replaced by the common PO black. Not very deep but easily felt by running fingers over them. Haven't noticed this occurring in modern helmets (but my riding style has changed too).
    -Speaking of the 60's, a local (Fort Ord) wives tale is that our Guv'ment bread strains of poison oak to deter and/or neutralize enemies. Possibly even deploy as a "natural" chemical weapon.

    So yeah, getting back to modern-day defeating/eradication of the evil-weed....

    #1 If you're building a trail - Just route the sum' biatch AROUND thickets of the stuff. Life will be better for everyone, especially those who maintain the trail.

    #2 As Woodrock has said - GO to the source of the vine when building/maintaining a trail. This takes a certain level of crazy and/or commitment. Personally, it is a GREAT feeling sawing through a TRUNK of an old-growth (if you will) poison oak vine/tree.

    #3 Cover-up! Dress appropriately. Have baby-wipes on-hand for post-work wipe down, then put your contaminated clothes in a bag, then in the wash ASAP. A little Technu in the wash never hurts.

    #4 Shower as soon as possible. Luke-warm water as mentioned before, scrup with a wash clothe, I prefer to spend the $$$ on Zanfel and use it sparingly to make it last and ONLY use it on spots you know could have come in contact. This way your $$$ product will last longer!

    -Personally, I don't have evidence of exposure/rash for a couple of days after contact BUT if I know I rode through a known patch of oak see tip #4!!!

    Again, get out there people and trim back the stuff while it's young & not at full-leaf!!! Your efforts will be appreciated by all!!!
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    Quote Originally Posted by DMFT View Post
    -Speaking of the 60's, a local (Fort Ord) wives tale is that our Guv'ment bread strains of poison oak to deter and/or neutralize enemies. Possibly even deploy as a "natural" chemical weapon.

    So yeah, getting back to modern-day defeating/eradication of the evil-weed....

    #1 If you're building a trail - Just route the sum' biatch AROUND thickets of the stuff. Life will be better for everyone, especially those who maintain the trail.

    #2 As Woodrock has said - GO to the source of the vine when building/maintaining a trail. This takes a certain level of crazy and/or commitment. Personally, it is a GREAT feeling sawing through a TRUNK of an old-growth (if you will) poison oak vine/tree.

    #3 Cover-up! Dress appropriately. Have baby-wipes on-hand for post-work wipe down, then put your contaminated clothes in a bag, then in the wash ASAP. A little Technu in the wash never hurts.

    #4 Shower as soon as possible. Luke-warm water as mentioned before, scrup with a wash clothe, I prefer to spend the $$$ on Zanfel and use it sparingly to make it last and ONLY use it on spots you know could have come in contact. This way your $$$ product will last longer!

    -Personally, I don't have evidence of exposure/rash for a couple of days after contact BUT if I know I rode through a known patch of oak see tip #4!!!

    Again, get out there people and trim back the stuff while it's young & not at full-leaf!!! Your efforts will be appreciated by all!!!
    good advice!!!!
    IPA will save America

  16. #116
    fc
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    The armageddon is here. 4 days of 70 degree plus weather and all that rain have fueled this monster.

    We feel so hot too so most folks shed their arm and knee warmers. I bet you a LOT of riders are scratching this morning!
    IPA will save America

  17. #117
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    It's going to get real here quickly!

    I already got 2 small patches from riding Auburn then Montana De Oro and there were barely any leaves present. Hard to avoid the stuff when bombing down hill at warp speed.

  18. #118
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    Quote Originally Posted by JCWages View Post
    It's going to get real here quickly!

    I already got 2 small patches from riding Auburn then Montana De Oro and there were barely any leaves present. Hard to avoid the stuff when bombing down hill at warp speed.
    Oh...was that you on East Boundary trail? We need to trim that.
    Always ride with a purpose.

  19. #119
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    Quote Originally Posted by dirtvert View Post
    It's going to be a rough year for folks that get p.o. I usually ride one of my favorite trails in SC solo because it's pretty much impossible to avoid. Tahoe Matt followed me down it in early Feb. and, even though it hadn't even leafed out yet, he still got a few patches.
    With the weather we've had, I doubt that any one of us will NOT be touching poison oak this year!

    Quote Originally Posted by dirtvert View Post
    My g/f manages it with Dawn-infused paper towels immediately post-ride, then a Dawn scrubdown in the shower.
    I glob the stuff on. Either Dawn or Palmolive (whatever is cheaper at the time at Costco).

    Quote Originally Posted by dirtvert View Post
    I saw a video last year of a guy back East that had studied poison ivy and did lots of trailwork involving it. He showed himself handling it, so it seemed to work for him.

    Found it: https://youtu.be/4oyoDRHpQK0
    Thanks for finding that video.

    The "axle grease" analogy is interesting, although I've never felt "greasy" after being in poison oak, but I also didn't touch the sap on purpose either. Certainly "pine sap" is a sticky mess.

    Is there a "sap" we can touch, that is common out here, that can be an analog for how "greasy" the poison oak sap is?

    I agree (for the most part) with the guy who said that if you understand it, you don't need to fear it. He, like I, don't think we need to buy expensive products to prevent the rash.

    He liked the Dawn, but he liked "abrasives" better (he called it "friction").

    Rubbing with the cloth makes sense (which is why I suggested toothpaste in an early post) since the urushiol is already through the first two layers of the epidermis and subsequently oxidized to a quinone and probably already bound to a protein which itself might already be bound to a langerhan's cell by the time you start washing (and certainly by the next day).

    Washing with the washcloth is to give you the "friction" to abrade the skin to get "down" to where the bound quinone is, is the suggestion in the video (without saying so explicitly).

    He didn't mention it, but that's when the polyethylene glycol spermicide comes in handy too, because it's a tiny surfactant that reputedly trades the bound quinone for itself.

    Anyone know where we can get cheap spermicide in bulk?

  20. #120
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    I've been attacking huge freaking bushes of PO on my property this year. I'm very allergic. I've been using a pole pruner on the trunks and a tractor with loader bucket to move/smash bushes, in places I can get the tractor in. I found that guy's video a few months ago and I've been practicing that after every PO eradication session. Dawn and scrubbing with a washcloth. It seems to work. I still get a little, probably secondary exposure from not being careful enough removing clothes or cleaning my equipment, but it's not been bad.

    I've been trying to do what I can before the leaves start coming out but that will happen any day now. I think then I'll get the full Tyvek suit and also break out the chemicals.

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