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Darn Tough Socks with Insect Shield: Make Your Own

Darn Tough Hiker Socks with Insect Shield

Wouldn’t it be great if you could buy Darn Tough Hiker Boot Socks with Insect Shield to protect yourself against Lyme disease-carrying ticks? Unfortunately, you can’t, but you can take matters into your own hands and send your socks out to be treated with Insect Shield. That’s what I do each spring at the start of hiking season.

Lyme Disease Prevention

What’s the one place where Lyme disease-carrying ticks have unfettered access to your skin. Your feet and shins, of course. While you can wear long pants, they still won’t protect your shins, calves, ankles, or feet, particularly if you wear trail runners or hiking shoes for hiking.

A better solution is to treat your socks with Permethrin, the active ingredient in Insect Shield. Used by the US Military, Permethrin is an insecticide that bonds to the fabric of your clothing, killing insects that land on it, including ticks and mosquitos. While you can apply Sawyer Permethrin to your clothing by yourself, it only lasts for 3 washes. The advantage of the Insect Shield Treatment is that it will last for 70 washes, which is particularly good for garments that you get wet nearly every day on the trail, like socks, in stream-crossings or rain.

The Insect Shield Treatment is already used on many of the hiking clothes I wear including:

As far as I’m concerned, the most dangerous animal on any other hiking trail is a Lyme-disease carrying tick. I’m willing to take great precautions to avoid contracting Lyme disease, and sending my socks out for an Insect Shield treatment is a necessary precaution in my mind.

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  1. Be nice if that service was available in the UK.
    I just sprayed mine with Premethin for the TGOC nect week.
    Also sprayed the bottom of the trousers and waist belt of the trousers too.

  2. Is it a wise idea to treat all sneakers/shoes with permethrin? Since I don’t wash my shoes/sneakers I feel the 1 permethrin treatment would last the season and while the insect shield is great idea for socks no reason to pay for shoes/sneakers that don’t get washed.

    • My shoes get wet very frequently during stream crossings and hiking in the rain. Spray on permethrin only lasts 3 washings. I think the 70 washing treatment on socks is the way to go.

  3. How have the tics been so far on the AT?
    Have you noticed a difference between hikers with Permethrin treatments vs those without?

    • I’ve seen some ticks land on my gear and clothing in Northern Virginia. it only takes one. The locals are surprisingly aware of the problem down here, especially the scoutmasters I ran into. Some thru-hikers and section hikers too, who are hiking with permethrin treated clothing.

  4. I ordered 36% Permethrin on amazon, 32oz for $23. Diluted down to the 0.5% in the Sawyer brand makes over 2300 ounces.
    10% is also sold at Tractor Supply and other local stores.

    • That’s nice but it only lasts for 3 washings. If you send it away to Insect Shield it lasts for 70 washings, which is essentially the lifetime of the garment (70 weeks on trail).

      • I think you are wrong there Phillip. After you dilute the veterinary Permethrin concentrate, you soak your clothes in it. The concentrated Permethrin binds to the fibers in the same way that Insect Shield does, and lasts many times longer than the spray Permethrin from Sawyer. I believe you get virtually the same lifetime from soaking as you get from Insect Shield as that is all they do to your garment.

  5. Depending on where you started/ended your hike you may have been in the CDC hot zone. Once you hit SNP it gets pretty bad.

  6. Sent some of my Darn Tough and clothing for InsectShield treatment after reading your earlier post. Does the treatment have any affect on black flies? We will be hiking hut to hut with some zeroes at lodges from Franconia Notch to Gorham in mid June . Any ticks on that route

  7. Maybe the snow still in Scotland will be good, because the Monadhliath in central Scotland are normally pretty endemic with deer and tics.

  8. That’s nice, lasts 6 weeks, not 3 washings… I guess i missed the 70 weeks part…

    I called Insect shield. They use .052% Permethrin. Sounds like they just do a military soak and a tumble dry to set the permathrin, vs an air dry like the Sawyer method.

    Soaking, air dry then repeat will probably give a longer life

  9. InsectShield is awesome — I bought a pair of ExOfficio hiking pants with it early last year which I used extensively dayhiking, including bushwhacking, in the Mid-Atlantic in all four seasons. We pretty much have ticks year round. I found one tick on my pants the whole year and it literally fell off dead as I watched it. I bought an InsectShield shirt after that. Great idea re sending the socks off to get treated!

  10. Low gaiters, with your long pants tucked inside, will solve that problem. No insecticide needed (although I do use it)! I prefer not to have insecticide on my socks, particularly the part on my feet inside my shoes.

    Back in the days before permethrin and when the main risk from ticks was Rocky Mountain Spotted Fever (I had to get 4 “shots” per year, every spring), we were shown movies in school that told us to keep long pants tucked into socks and long sleeve shirt tucked into pants, with insect repellent at wrists and neckline. We were told that we’d feel the ticks crawling if they got to our necks and could brush them off. Eeek! I can feel them crawling right now!

  11. Keep in mind what you are embedding into your clothing. Permethrin is not a repellent, it’s a neurotoxin and is extremely toxic to fish, cats and invertebrates. It it not known to effect mammals or birds. Do not use it if you spend any time in streams or lakes.

    • I was wondering about the same thing. I don’t mind killing ticks (the more the merrier) but I am reluctant to apply Permethrin to my footwear and socks. Crossing streams is inevitable on the AT, and doing so will inevitably release the toxin into the water, affecting the fish. So the blanket enthusiasm for Permethrin presented in this blog might be a bit overboard? Or is the 70-cycles shield version indeed significantly less likely to leech into the water than the Sawyer spray-on version is?

  12. Here you are:
    “Health effects of permethrin treated battle dress uniforms”
    Darn little toxicity, and the experimental animal toxicities are at doses that far exceed (orders of magnitude) any human exposure short of drinking the stuff.

    I consider this a wonder drug that saves my sleep and my sanity as well as protects me from the tick-borne diseases. Chiggers are abundant everywhere I hike here in the Ozarks from May to hard frost. You only need to get one experience without adequate insect/mite repellent to be convinced – the chiggers like to bite where the sun don’t shine, eg intergluteal cleft (*ss crack) and genitals. And I just hate using a lot of DEET because DEET dissolves the engineering grade plastic on cameras and lenses, and photography is a big part of hiking for me.

    The washing issue is that the home-applied permethrin can be leached by extensive agitation in the washing machine. A mere rinse and hang doesn’t dislodge much permethrin. I don’t worry about crossing streams. The Insect Shield method attaches the permethrin more firmly so it resists washing machine agitation.

    I bought an “Insect Shield” treated sleeping bag liner for those 75 degree low sticky humid nights when I skip a bag and sleep in the liner.

    • I’m amazed that people are so eager to soak their clothes in such an incredibly effective pesticide, and go tromping through wild areas, without a thought to possible side effects.

      Of course you’ll find studies by the dozen that find no link between permethrin and human disease. Otherwise it would not be around for your use. But if it’s causing environmental damage, who knows when we’ll realize it, and someone decides to do a study to prove it.

      • With the amount of sweating and direct contact I for one wouldn’t soak my socks in the stuff.

        The military has been using it for years and most uniforms are factory treated. I think I’m going to treat my only a few outer clothing items. Also my backpack tent etc.

        My dogs tick spot treatment is 44% Permethrin so I’ve definitely been exposed to higher doses than the 0.5% that clothing is treated with.

        I don’t know if deet is even safe but ticks and black flies suck.

      • If the bugs are not in contact with you, they do fine. I suppose the real question is not how much permethrin is getting in the water run-off from our home washing machines, but how much is getting in the water from industrial and agricultural uses. I am not going to worry about a few molecules getting loose from my pants and socks. There are enough hunters and farmers and hikers getting serious tick-borne diseases locally that some prevention is necessary. I would think that DEET, needing fresh application daily or every few hours, at high concentrations, would be more of an issue. And DEET at low concentrations doesn’t work for ticks, you need the 100% stuff.

        As I said before, permethrin is now part of civilized life for those who engage in summer outdoors activity. Chigger itching and fresh bites may persist for a week after an outing, you can’t see the darn things, and trust me, once you have gotten a crop of chiggers biting where the sun don’t shine, you are not a fun person to be around.

  13. Question for Phil or anyone else who has thought about this: I’ve got Insect Shield pants and shirts and I spray my hat and socks. I should get a mosquito headnet, though, and I’m a little shy about putting an insecticide right where I breathe. Is anyone who understands the chemistry of this stuff confident about using it on their face? Thanks.

  14. The Sawyer Permethrin is actually good for 6 washes or 42 days, at least according to my bottle. It says items should be retreated after 42 days regardless of the number of washes.

  15. Hi Philip!
    Have you noticed any shrinkage with the Darn Tough socks you’ve sent to Insect Shield, or any other article of clothing after you get it back from Insect Shield?
    I’m thinking of sending the Ex Officio Performance Hoody to Insect Shield for a treatment, and I’m hoping it won’t shrink in the process. The Hoody is 91% nylon and 9% spandex. Do you know if nylon shrinks if heat is applied to it (it’s my understanding that the process of applying Permethrin that Insect Shield uses involves subjecting clothing to heat)?

  16. I have Buzz Off Socks. When I wear them against my skin I get bad foot cramps. I cannot find anything about this online. I have to wear untreated stockings under them to not have this happen. I have a hard time believing Permethrin is actually non-toxic.

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