Core Backpacking Clothing || Go Suit — Items 1-2: Short- & long-sleeve shirt

My Go Suit on last summer's Wind River High Route attempt: bug shirt, underwear, and stretch woven nylon pants. Photo: Peter Bakwin.

My Go Suit on last summer’s Wind River High Route attempt: bug shirt, underwear, and stretch woven nylon pants. Photo: Peter Bakwin.

My Go Suit is my backpacking uniform, and I wear these clothing items every day from sunrise to sunset — and, unless they’re wet, at night too. Additional layers from my “Stop” and “Storm” categories are worn over them, while my “Sleep” layers replace them when wet for improved nighttime comfort. Out of the Core 13, a tight collection of backpacking clothing, my Go Suit constitutes the first 7 items:

When my Go Suit becomes unacceptably dirty, I do the same thing as I would at home: I do laundry, usually in the backcountry with just water (no soap), in order to remove dirt, salt, and some stink. No spare or extra clothing. I definitely could get a cleaner clean with a washing machine and some detergent, but a backcountry wash is an effective interim solution.

Overlooking the South Fork of the Kings River from Tablelands, wearing Sierra Designs L/S Pack Polos.

Overlooking the South Fork of the Kings River and the Monarch Divide from Tablelands, wearing Sierra Designs L/S Pack Polos.

Items 1 & 2: Short-sleeve & long-sleeve hiking shirt

In warmer weather, I normally wear the short-sleeve shirt. In cooler temperatures, and/or when I need to protect my arms from scratchy brush and relentless sun, I wear the long-sleeve.


Other than sleeve length, the shirts can have identical specs. Look for a knit polyester or merino wool fabric labeled “silkweight” or “lightweight,” or a weight of 120 g/m2 to 150 g/m2 (for merino fabrics only). If the shirt will be used only in hot, arid environments, a cotton component is acceptable — if not actually desirable — for superior airflow and extended evaporative cooling.

Avoid woven fabrics, which normally have low airflow. (Quick comparison test: Put your mouth against the fabric and strongly exhale.) And avoid nylon, too; it’s a very durable synthetic fiber, but it does not manage moisture as well as polyester. Oddly, many of the button-front “travel” shirts popular with hikers such as the REI Sahara Tech Long-Sleeve  feature both. While such shirts are generally more UV-resistant than knits, the benefit is marginal: a knit shirt with a UPF rating of 25 still blocks 96 percent of UV, versus 98 percent for a much stuffier woven shirt with a UPF rating of 50.

I generally prefer merino wool because it’s far more odor-resistant and it’s warmer when wet (though not “warm”). But I can make an argument for polyester, too: it’s much less expensive and more durable, absorbs less moisture and dries faster, and can be milled in lighter weights, which makes it cooler and a better moisture manager than the lightest wool fabrics. Also, in dry environments I find that polyester is much less offensive smelling, especially with a backcountry wash every two or three days.

Fit & features

The cut should be regular, since a semi-fitted or form-fitted shirt will be too warm. A slightly long torso will prevent the shirt from riding up and allowing a backpack to chafe your lumbar. To supplement the air-permeability of the fabric, I like venting features like a chest zipper or button-front. To protect my neck from the sun, I want a high collar, not a crew neck. Finally, I want to look sharp when wearing it; I avoid poor-fitting, slopping-looking “base layer” underwear.

Closeup of a knit synthetic (red) and knit merino (blue). Each fabric type has pros and cons. Note the holes in the merino due to wear.

Closeup of a knit synthetic (red) and knit merino (blue). Each fabric type has pros and cons. Note the holes in the merino due to wear.

My picks and suggestions

Ibex Echo Sport Zip T Short-Sleeve. The fit and features of this shirt are perfect, but sadly it has been discontinued and I can’t find an exact replacement. Any suggestions? Like all pure merino shirts, its durability and moisture management were lacking versus my synthetic shirts, but I loved its 150 g/m2 weight, regular fit, mid-height collar, and chest vent. As a substitute, I’d probably pick the Icebreaker Quattro Polo, which besides the button-collar is almost exactly the same; or you might be happy with the simpler Icebreaker Tech T-Shirt (women’s) or similar.

Sierra Designs Short-Sleeve Pack Polo and Long-Sleeve Pack Polo. I wore the long-sleeve version for a month straight last summer in the High Sierra and loved it: awesome air flow, super fast dry time, and good looks.

If I were in the market for a long-sleeve merino top, I’d take a look at the Stoic Alpine Merino Bliss Shirt and the Icebreaker Aero Half-Zip Shirtwhich appear to have the right fit and features. Both also have a synthetic fiber component, which improves moisture management and durability while reducing the cost.

Sierra Designs Long-Sleeve Pack Polo (red) and Ibex Echo Sport Zip (blue). These exact shirts, or shirts with similar fabrics, fit and features, serve well as short- and long-sleeve hiking shirts.

Sierra Designs Long-Sleeve Pack Polo (red) and Ibex Echo Sport Zip (blue). These exact shirts, or shirts with similar fabrics, fit and features, serve well as short- and long-sleeve hiking shirts.

Posted in on March 9, 2015


  1. Charles on March 10, 2015 at 4:34 am


    When you wash your clothing in the backcountry, what is your process? Water only? Do you Use any soap (toothpaste)? Do you have a preference where you hang them to dry?


    • Andrew Skurka on March 10, 2015 at 8:43 am

      “I do laundry, usually in the backcountry with just water”

      I thought this would imply “without soap” but I updated the post for clarification.

      A few options for drying:
      1. Wash, wring, and put back on. Sometimes feels great, sometimes cold, but whatever it’s the fastest way to clean and dry.
      2. Wash, wring, put on a rock, lay over some vegetation, or suspend in mid-air using my trekking poles. Rarely will I wait around long enough for things to dry completely, but maybe long enough that they reach ambient air temp instead of snowmelt temp.

      Normally I was mid-day when the temps are highest and when I probably could afford a 30-minute break anyway.

  2. Jorgen Johansson on March 10, 2015 at 7:46 am

    A long time favorite of mine that have the same specs (merino, short sleeve, collar, looking sharp) as those you, a lot like the discontinued Ibex, is Icebreaker Kent Polo. It is 190 g/sqm, however.

    • Andrew Skurka on March 10, 2015 at 8:44 am

      I looked it up. Here’s the link: Icebreaker Kent Polo. Indeed, a good looking shirt.

      Icebreaker appears to have a newer equivalent, the Icebreaker Quattro Polo Shirt. But it’s 150 g/m2 weight, which is ideal. There’s a little bit of spandex (4%) but I’d still spring for this. In fact, performance-wise it’s going to be very similar to my recommended Ibex. I might actually update the post with this product.

      Since we’re on the topic of merino polos, I also own this: Ibex Ace Shirt. My conclusion is that full-length buttons are a tough sell for lightweight merino — the fabric does not have enough rigidity, so there is a wave pattern down the front, not clean-looking at all. The few buttons on a polo should be okay, though.

  3. Vadim Fedorovsky on March 10, 2015 at 7:48 am

    Andrew will your picks and suggestions above offer the necessary bug resistance? I have always sworn by long sleeve nylon travel shirts b/c of their bug resistance.

    Is it not true that bugs can easily bite through merino and poly?

    • Andrew Skurka on March 10, 2015 at 8:59 am

      Yes, bugs can easily bite through knit merino and poly. However, when bugs are not an issue I would much rather have the superior airflow and moisture management of these fabrics.

      A bug shirt is Item 3 in the Core 13 and will be discussed tomorrow.

  4. Helen J. Gauperaa on March 10, 2015 at 8:07 am

    Will you ask Amanda to chime in with her recommendations for women, too? Icebreaker do the equivalent female cut to their men’s models, but I’m not so familiar with the other brands you mention to know whether similar exists for women. Thanks!

  5. Tara on March 10, 2015 at 10:02 am

    I splurge on Ibex when I can afford it. I have had the Ibex Ace for many years and it is still going strong.

  6. Simon on March 10, 2015 at 10:26 am

    I use a Nike Pro Combat compression tee shirt for first layer @ 4oz’s or an Under Armour cold ygear long sleeve mock @7oz’s. For sun protection on the arms with the short sleeves I use some Nathan SPF 50 spandex compression sleeves. Paired with second layer Mammut Prussic wind jacket at just about 3oz’s I have a solid 7-10 ounce heat preserving wind proof, sun proof bug proof top system.

    • Andrew Skurka on March 10, 2015 at 1:01 pm

      What is the air-permeability of that Mammut wind shirt? If it’s like other wind shirts, I can’t imagine that it’d be comfortable to wear in warmer temperatures over a hiking shirt. A dedicated bug shirt (the subject of tomorrow’s post) would be a lot more comfortable for all-day wear.

  7. clay on March 10, 2015 at 11:42 am


    Does it help you – financially or otherwise – if I click through with the links you provide, as opposed to say, going directly to the Ibex or Backcountry sites?

    I ask because I use Ghostery to prevent the hundreds and hundreds of “analytics” and other widgets from tracking my activity on the internet.

    I can allow one-time click-through via Ghostery if it helps you out.


    • Andrew Skurka on March 10, 2015 at 12:59 pm

      Only if you buy something. If you get value out of the information provided, and wish to support my efforts by allowing the vendor to know that I may have helped to initiate a sale, please do. Otherwise you’ll have to use Ghostery or similar, or clear your cookies regularly.

  8. David Eitemiller on March 10, 2015 at 4:13 pm

    I have been really happy with the Patagonia Merino products. Merino 1 (silkweight) and Merino 2. Wore the Merino 1 LS in the Sierras in September and it was fine even though it didn’t have a neck vent. The sleeves pull up and stay unlike a lot of other LS shirts and made it easy when temps cooled in the evening.

    In cooler temps the merino 2 is good and has zip neck for when temps warm or you are headed up an ascent. Granted neither of these have collars so guess that disqualifies them for the perfect 13 ranking, but worth a mention.

    They are pricey though, look for sales, it costs to wear Yvon Choinard’s name!

  9. Lee Tintary on March 10, 2015 at 7:26 pm

    I use a long sleeve Smartwool microweight long sleeve year round as my hiking shirt. It has served me well as a single layer on the move in 40-90 degree temperatures. I prefer long sleeves to sunblock. I couldn’t find an acceptable wool bottom, so a few years ago I bought wool gabardine cycling knickers. They were handmade by a tailor in Oakland and were expensive, now prohibitively. If I am bushwhacking or know I will be in wetter environments, I will switch these out for the Mountain Hardware Canyon pants. This with the Smarwool microweight boxer briefs, a Sunday Afternoons hat, Smartwool PhD socks and dirty girls takes care of 90% of my needs on the trail. Probably less now in Portland than So Cal.

  10. Matt S on March 10, 2015 at 8:35 pm

    Nice, keep the articles coming!

  11. Dave F on March 11, 2015 at 9:40 pm

    I’m a huge fan of the Rab Meco stuff, which is a 65/35 blend of merino and polyester. I currently have 120 weight short and long sleeve tees, 120 pants, and a 165 hoodie (for cold weather) that I’ve been really impressed with. Dry times are way better than 100% merino but it still wears like wool. They have a 140 zip tee that would probably compare to the Stoic and Icebreaker shirts you mentioned. A little on the expensive side (think merino, not synthetic), but I waited until it was on sale and got it for synthetic prices. I had some issues with the stitching on one of the shirts but that was easily fixed… so far it’s been worth the trouble. Highly recommended.

    • Andrew Skurka on March 12, 2015 at 6:40 am

      I have two pieces that are blended merino/polyester and I also think they perform really well. Maybe this is the ultimate happy-medium.

      On its own, pure polyester can stink so badly to almost be unbearable, especially in wet and humid climates when the bacteria can really fester. But otherwise it’s the superior fiber — quicker dry time, better wicking, more durable, less expensive.

      On its own, pure merino is highly odor-resistant but it is inferior in nearly every other regard — slower dry times, poorer wicking, and more expensive. The only other thing it does well is keep the wearer warmer when wet (though as I pointed out earlier, not necessarily warm).

      By blending some amount of poly in with merino, the performance characteristics all seem to rapidly improve while still retaining merino’s anti-stink and warmer-when-wet properties. I’d love to see more manufacturers fill this niche.

      • Geoff on March 13, 2015 at 4:10 pm

        The polyester in MeCo has some kind of activated carbon incorporated to help with wicking and odour control. Works well for me, and seems to work well for others too if you can believe the reviews. I now greatly prefer it to pure merino, and I’ve been using merino since the ’60s.

        In the last couple of years I’ve been a convert to the Brynje Super Thermo – a kind of technical string vest. It has real pedigree, including the Norwegian army and the first summiting of Everest. I wear it on my skin capped with the merino, and it’s been a brilliant combination. Speeds up venting when you’re warm, adds thermal efficiency when you’re cold, keeps wet merino off your skin and dries in minutes. No problems with odour either. Highly recommended.

        • Andrew Skurka on March 13, 2015 at 5:11 pm

          I have a few Brynje tops but have never really figured out of to best integrate them. You use yours in warm weather? My impression is that they are a cool/cold and cool/cold-and-wet piece.

  12. Aidan B on March 12, 2015 at 3:47 pm

    Hey Andrew,

    Do you have an opinion in regards to the colors of the base layers that you choose? As in, do you find any benefit for lighter colors for decreasing how hot it feels in the sun and vise versa?

    • Andrew Skurka on March 13, 2015 at 3:43 pm

      My long understanding has been that dark colors attract more heat. I’m sure this is true with hiking shirts too, but I’ve never tested two shirts of different colors to determine if the effect is actually noticeable. In general I stay away from dark colors, but not because of heat attraction — rather, they don’t make for very good photos.

      I’ve also heard (perhaps from a definitive source, can’t remember) that bugs are attracted to brighter colors. It’s a good reason to head out for an Alaskan epic wearing khaki pants and a gray long-sleeve shirt.

  13. Daniel on March 13, 2015 at 5:05 pm

    On BPL they were chatting about the Paradox Merino blend at Costco, at that time Costco moved there supply to Australia because it was winter, so for $22 Aud, I couldn’t resist and bought a few tops and bottoms, they perform well for a fraction of the cost of the named brands.

  14. MW on March 18, 2015 at 5:15 pm

    Thanks for the helpful roundup. 1) Since pure merino is definitely warmer than polyester, for lightweight blended merino-poly shirts like the Stoic Merino Bliss L/S Zip Shirt, how hot is too hot for them in summer? 2) Since – bummer – the SD Long Sleeve Pack Polo isn’t available, what are some currently available polyester L/S tops you like with UPF 25 and up and standup collar? What about Patagonia Capilene 1 Silkweight L/S shirts which are supposed to have a 50 UPF? Only thing they’re missing is a standup collar and zip/buttons, but perhaps with such light fabric you don’t need the collar venting.

    • Andrew Skurka on March 19, 2015 at 8:19 am

      “Too hot” will depend on your heat tolerance, sun exposure, and the humidity. In the West, I wear a longs-sleeve all summer because it’s worth keeping the sun’s radiation off my arms. If I were back east, short-sleeve or even a tank top all the way.

      No suggestions on a synthetic long-sleeve top with the SD Pack Polo going the way of the Dodo Bird apparently. The collar is a critical feature IMO, for the sake of sun protection. A normal crew neck leaves a lot of neck exposed. So long as the shirt has good air-perm, a chest vent is not critical, but a vent is always going to be cooler than fabric good air-perm.

  15. Beth on April 5, 2015 at 4:05 am

    Any opinion on this:

    Arcteryx Phase SL zip. Silkweight. Silver ions for odor control.

    (Phasic™ SL—70% polyester, 30% polypropylene, UPF 25, 98 g/m². Reduced yarn size of polypropylene lends soft touch to 100% hydrophobic jersey knit textile with mechanical stretch. Composed of multidimensional polyester yarns that wick moisture laterally to dry quickly, plus polypropylene yarns that have silver-ion encapsulated into the fibre for long-lasting odour control. Very light weight with a smooth outer face that slides easily under other layers.)

    • Andrew Skurka on April 5, 2015 at 9:37 pm

      Any hiking shirt made of polyester and/or polypropelene is going to smell from use. Product copy that makes claims of odor-resistance is at least a giant stretch, and quite possibly an outright lie.

    • Dave F on April 9, 2015 at 1:56 pm

      I have their Motus crew t-shirt, which I’m pretty sure is the same material… really comfortable shirt but if there really is silver-ion whatever in it, it’s worthless. It definitely stinks after a long day of hiking. You’ll get a little further with it in dry climates vs. east coast humidity, but I wore mine on a week long trip across Yosemite and it had an odor on day 2.

      For that price you can just as easily get a merino base layer, or the Rab Meco shirts I mentioned in a previous comment. I still wear the Motus shirt on weekend trips since it’s comfortable and I got it on clearance, but for anything longer I’d go with something different.

  16. Lander D on April 17, 2015 at 1:41 am

    Just wondering if you know much about the fabric ventile. I was thinking of making a custom shirt out of it and using it as strategy to help keep from getting any more wet than I have to in prolonged rainy weather.

  17. Mike on May 16, 2015 at 9:50 am

    I’d echo the suggestion of a merino-poly blend; the Patagonia Merino 1 is the best one I’ve found to date- it’s a 65% merino and 35% capilene blend, you get the warmth/comfort of merino, but it dries quicker and is more durable than 100% merino

    it’s offered in both short (4.7 oz in M’s Large) and long sleeve (5.7 oz M’s Large)

  18. Eric Blumensaadt on June 8, 2015 at 8:05 pm

    I actually LIKE my polyester woven, button front shirts like REI’s Sahara. I’ve used them over long sleeve poly long handled shirt for warmth or as a wind shirt, whether alone or over a knit shirt. Yeah, poly woven shirts are not as breathable as a knit shirt but I’ll put up with that so it can serve other purposes mentioned above. (NOTE: I do not carry – or own – a dedicated wind shirt.

    The mesh, vented back of most of these light poly shirts is nice, even under a backpack. And my Cabela’s Guidewear poly shirt has vented chest pockets.

  19. Sean on July 1, 2015 at 5:47 pm

    Just picked up the Stoic long sleeve merino which was on insane sale for 34 bucks over at steepandcheap.

    That is a *nice* shirt. A touch scratchier than Icebreaker (I suspect that will change with washing) but really a comfortable shirt and it dried after washing at night in about 3-4 hours in about 70% humidity. I was impressed.

  20. John Davison on August 27, 2015 at 4:12 pm

    “When my Go Suit becomes unacceptably dirty, I do the same thing as I would at home: I do laundry”.

    But how do you get it dry? Even in good weather quick-drying items could take half a day to dry, but in most weathers they’ll take longer (I live in England, BTW).

    And, with no spare clothing, what do you wear while the washed items are drying? If you dry them with body heat, by wearing them, that seems a quick route to hypothermia.

    Can anyone give me an idea of how I might take only one set of clothes, and wash and dry them occasionally? How does this work in practice?

    Many thanks.

    • Andrew Skurka on September 3, 2015 at 8:46 am

      Never do I wash the items and then let them dry completely. I wash them, let them come up to ambient temperature, and then put them back on. Body heat will help dry them out much more quickly.

      It helps, too, that I do most of my backpacking in relatively arid environments.

      If conditions are such that being partially or fully naked would lead to hypothermia, I’m unlikely to launder my clothes, or need to.

  21. JohnH on October 31, 2015 at 3:26 am

    For many years I’ve hiked in Lowe Alpine Dryflo or Paramo Cambia shirts. These are both long sleeve, high neck, deep zip base layers. Sometimes the only shirt I will have with me, very fast drying, especially for the “wash and go” technique of enroute laundering. They work from 20F – 100F, not too pongy, but no exciting colours at the moment.

  22. Justin on April 17, 2016 at 6:47 pm

    A note about polyester vs nylon. Nylon can be made just as breathable and wicking as polyester–it’s just not common yet. I have a Under Armour Iso Chill ls, hooded shirt that is made out of a knit, nylon and elastane blend. It is very breathable and quite wicking.

    I prefer nylon over polyester for warm to hot weather, especially if it’s humid, because nylon doesn’t smell as quickly, intensely, and it’s easier to wash it out more completely. Nylon, when more breathable, seems to be slightly cooler on the skin. It’s also tougher at lighter weigh.

    But i also am not a fan of the typical nylon supplex button up type shirts, because they lack breathablity and most aren’t that well wicking–i tend to feel clammy in them. The one good thing about them is that they are good at blocking insects more completely than any knit shirt, but a windjacket can also address that.. Some companies are starting to address the lack of breathablity and wicking of nylon button up shirts, like Kuhl’s Wunderer shirt, which is a bit more breathable than the older ones, and utilizes permanent wicking nylon fibers (whereas some companies like REI’s Sahara uses a finish that will eventually wear out).

    Besides the U.A. shirt, other knit and well wicking mostly nylon shirts are the ones made by Duluth Trading (technically classed as “undershirts” i believe). Haven’t tried them yet, but have heard good things about them from folks i respect.

    What i’m really enjoying of late, are nylon tencel blends. Still tough, dry fast enough in all but the most humid and hot conditions, well wicking, great at odor control, cooling, just tightly woven enough to block most bugs most of the time, but usually a bit more breathable than the typical, older all nylon button up shirt. I wouldn’t wear any of the above for winter, or consistently cool and wet conditions though, all the above are too cooling in nature. For the latter conditions, i either wear polygiene treated Cap 4 type, high void grid fleece, or Merino or Alpaca and synthetic blends.

  23. Ben on April 21, 2016 at 2:09 pm

    Andrew – Thanks for the great write-up. Read today, and clicked through the links you provided, then went straight to the source (SD).

    Thought you might appreciate this link if it hasn’t been provided to you before (seeing as how this article was written a year ago) regarding the long and short-sleeve pack polo.


    In no way affiliated with SD, or any clothing manufacturer for that matter. Just thought I’d pass along for anybody else who reads this article for the first time.

  24. rj on July 4, 2016 at 8:42 am

    Are the Sierra Design long and short sleeve shirts back?

    I can’t tell the specs on their site if this is what you were referring to

    Cheers RJ

    • Andrew Skurka on July 4, 2016 at 10:53 am

      Yes, that’s the one. Looks like the links had broken since I first published the post, so I updated it.

  25. Mark on July 5, 2016 at 2:47 pm

    Hey, Andrew. A question about your comment on polyester and smell. I live in Texas and get to camp and hike mostly in warmer months. I’d like a new long-sleeve shirt for camp use and day hikes. Since I sweat a lot, should I try to avoid shirts with ANY polyester or just shirts that are mostly polyester. For instance, the Sierra Design Solar Wind shirt seems pretty neat, but the back is a poly blend.

    I like a button-down with chest pockets, so any other suggestions you’d have me consider would be greatly appreciated.

    • Mark on July 5, 2016 at 2:49 pm

      You will infer, presumably, that I’d like a take along a single long-sleeve shirt for a camping out or a couple of days on the trail, and that’s why something that doesn’t smell badly is nice.

      Other shirts I spotted in the no-poly line-up include the Kuhl Flakjak and Columbia Featherweight Hike.

      Thanks again.

    • Andrew Skurka on July 5, 2016 at 3:29 pm

      If your goal is to avoid stink, some poly is okay, especially if it is blended with wool. But a pure poly, even one with an anti-stink treatment like the SD shirt, will begin to take on an odor of its own.

      Nylon does not seem as offensive as poly, even though it’s also a petrol product. If you go with a traditional “trekking shirt,” that might work for you. However, these shirts tend to be tightly woven and have horrible air flow, which might make them intolerable for Texas.

      All in all, I think you’ll be best off with a poly/merino blend. The Patagonia Everyday Crew L/S is a good example, and it’s on sale right now; there is also a S/S, also available from Backcountry. You’re not getting the button-down and pockets, but this will be as anti-stink as you’ll get, unless you spend more on a pure merino shirt.

      Quite frankly, you’re asking for a shirt that does not exist: no stink with chest pockets. Actually, you might be able to fine a pure merino shirt like this, but I think you’ll be disappointed in the pocket performance — merino does not keep its shape like nylon does.

  26. Pete H on July 8, 2016 at 1:17 am

    Great article in a series of really great articles Andrew! I notice in the 13 items of clothing you don’t mention a dedicated ‘base layer’ as such, though I suppose once you add a fleece on top of this shirt then it kind of serves that function. Is it that this clothing set up is for milder conditions, and that base layers are typically of the ‘thermal’ variety, hence only needed in colder situations? You say above that the shirt is better than the ‘sloppy base layer underwear’ – which I’m guessing means that the merino shirts you favour are more loose and shirt-like than the tight base layers by companies such as Icebreaker and Smartwool?
    I must admit I get a little tired of the very close fitting ‘athletic cut’ designs and would be interested to try something more shirt-like.

    • Andrew Skurka on July 8, 2016 at 9:20 am

      For 3-season backpacking I think “base layer” is the wrong way to think about it. To me, base layer implies something that multiple other layers go over the top of. But in 3-season conditions, I spend nearly the entire day wearing only a single top. Seems like more of a standalone “shirt” at that point. And when you start looking for a shirt, you start looking for subtly different qualities: looser fitting, more stylish, and perhaps more resistant to sun, bugs, and brush than a conventional knit thermal top would be.

      • Jason Turner on July 13, 2016 at 7:21 pm

        new to this but really shopping for a moisture-wicking shirt that isn’t 100% polyester-I can stink them up in one afternoon of activity.

        Is this one that fits the bill?

        • Andrew Skurka on July 14, 2016 at 4:02 pm

          Patagonia Capilene is 94% polyester and 6% spandex. An anti-funk treatment has been applied to the polyester, which in my experience seems to help but which still does not put polyester on par with, say, merino or cotton.

      • Big Donald on April 22, 2018 at 3:22 pm

        I’m curious about this. I’ve always hiked in tight fitting “athletic top” type short sleeve, unless it’s cold enough to use a fleece. I hate looking like a gym bro, but the moisture management is really great and important for me. It’s usually below 50f wherever I hike and I get cold quickly.
        I did try a somewhat more aesthetically pleasing “hiking shirt” but the sweat management just wasn’t there.
        My understanding is that a “base layer” which has the primary purpose of managing sweat, does really have to be tight fitting to function (so that your sweat is evaporating from the fabric rather than your skin, which creates heat loss).
        Do you find your somewhat looser fitting hiking tops work well enough in managing this?
        My hiking is often combined with travelling, and for a minimalist set up my town clothes are also my hiking clothes and I’d sure like to blend in a little better 🙂

        • Andrew Skurka on April 22, 2018 at 8:01 pm

          A looser-fitting shirt should be more comfortable in normal 3-season conditions than a tight-fitting shirt, all else being equal. While it won’t wick quite as well (it won’t be in contact with the skin as much), you’ll get much more airflow through the shirt, which will assist in evaporation and in exchanging hot body-warmed air for cooler ambient air.

          Your experience may be due more to the two shirts that you used. If your “gym bro” shirt was made of loose knit polyester and your experimental looser-fitting shirt was made of tightly woven nylon, no doubt that the gym bro shirt would manage moisture better. But if you used a shirt made of the same material, you’d get a different result.

          My favorite hiking shirt for several years has been the SD Pack Polo (sadly discontinued), and it’s looser fitting. But it has crazy airflow, which makes it a great hiking shirt for warmer temps.

          • Big Donald on April 22, 2018 at 8:33 pm

            You’re quite right it could be down to the specific shirts I used. The “hiking” shirt I did use wasn’t ideal (didn’t dry very quickly and I sweat a lot, so I got cold very quickly). I will likely re-try a different shirt when the price is right.

            I’ve also wondered about using something like the mesh baselayers by brynje. Never really seen them mentioned but a couple of backpackers I know who hike in colder wet conditions swear by them. Would add very little warmth I imagine, so could be work fairly modestly under a more convention lightweight shirt with decent airflow, sun protection etc hopefully without getting too hot. Could be a way of getting the best of both. Or it might just be overcomplicating the process of wearing a top 🙂

          • Andrew Skurka on April 23, 2018 at 9:49 am

            The mesh tops are warmer than you’d think. They end up trapping a lot of air next to skin. I wouldn’t even consider wearing them for hiking in temps warmer than about 30, or maybe 40 if it’s raining.

  27. Brad R on January 4, 2017 at 2:58 pm


    Do you have any experience with the Arc’teryx Velox Zip Neck SS shirt? It looks very similar to the Ibex Echo Sport Zip-T, but is constructed of polyester. It’s lightweight and seems very breathable, however, I’m wondering how durable it is. The fabric appears like it might snag easily, unlike the Sierra Designs Pack Polo. BTW, I do most of my hiking on the Olympic Peninsula and North Cascades.

    Thanks, Brad R

    • Andrew Skurka on January 4, 2017 at 3:07 pm

      No experience with it.

      Polyester is generally more durable than wool, but it is known to pick and pill. The exact knit construction is responsible for that. I can’t make an educated guess about abrasion resistance from the online photos. Maybe some reviews will be more helpful.

  28. Matt on March 20, 2018 at 5:07 pm


    Looks like the long sleeve pack polo is completely out of stock. Do you know if Sierra has discontinued it or if they are going to bring it back? Thanks for all the great advice.


    • Andrew Skurka on March 20, 2018 at 9:10 pm

      Sadly discontinued.

      No replacement that I feel comfortable listing specifically, but I’m sure you can find something. I have not worn another hiking shirt in 3 years.

  29. Jud on July 11, 2018 at 1:09 pm

    Hi Andrew, thanks for the great post. I’m in the market for some lightweight merino gear and I’m finding that the cheaper and lighter options such as the Minus33 microweight shirt are about 12% nylon and 4% spandex in addition to the the 84% merino. I get the impression from some of your other posts that spandex retains too much moisture for a quick-dry application. I’ve been trying to gauge how much is too much, looking at different sites, etc, and 4% has been coming up as an acceptable limit. What is your take? Thanks for the excellent content and advice.

  30. Chris on August 5, 2018 at 12:56 pm

    Hi Andrew,

    In case you’re still looking for a replacement for your Ibex zip shirt, I just ran across this merino zip SS at the Icebreaker site, currently 50% off.

    It’s a blend- Body: 50% Wool, 33% TENCEL®, 12% Nylon, 5% LYCRA

    Looks pretty nice, like a cycling shirt w/o the back pockets, weighs 6 oz in a size Medium.

    BTW, just did a weekend section hike on the AT in my newly purchased Sierra Designs Pack Polo SS. Shirt worked like a champ, really pleased with it- so much so that I bought 2 more from Sierra Trading Post.

    I’m currently scouring the InterWebs looking for a LS Pack Polo.

    • Mike G. on August 22, 2019 at 6:27 am

      Let me know if you ever find that LS!

  31. Lukas on June 14, 2019 at 2:22 pm

    The Smartwool Merino 150 Sport LS Zip fulfills all the criteria and looks sharp.
    Regular fit, Merino/ Polyester blend 56:44, 150 g/m2, 1/4 zip collar and nice colours.
    Check it out here:
    I just ordered one from REI (to germany…)

    • Mike G. on August 22, 2019 at 6:31 am

      I second the Smartwool Merino 150 Sport. I think it does a nice job of blending the characteristics of synthetic and wool. A bit warmer than the BD Rhythm weight, but I feel it’s acceptable. Especially for cooler temps I think it’s perfect.

      One caveat I have…the back of the shirt and underarms are mesh. This leaves you exposed to insect bites. If insects are a mild concern, I will just use picaridin on those areas. If they are a heavy concern, you probably should go with a bug shirt anyway.

  32. Belle on October 3, 2019 at 3:55 am

    I’m confused. It says that Tencel/lyocell absorbs 50 percent more moist than cotton. But that it is warm because it wicks moist fast. But we are all taught that cotton kills. Will this fabric not even make us more vulnerable for hypothermia?

  33. Jose on February 2, 2020 at 7:36 pm

    Andrew, have you found an acceptable replacement for the Sierra Designs Pack Polo? I know there are a few long sleeve options, but I love having a collar for the extra sun protection and the durability that the Pack Polo has. Unfortunately, I only have one and my wife would like something similar.

    • Andrew Skurka on February 3, 2020 at 1:51 pm

      Patagonia Capilene LS Lightweight Zip
      OR Echo Hoody

  34. Kanishk on June 7, 2021 at 1:51 pm

    Hi Andrew,

    Thanks so much for these great and detailed posts! I’m a novice and really learning so much from them. I was going through REI’s store and found this great shirt which is also bug repellent. What do you think of it?


    • Andrew Skurka on June 7, 2021 at 2:10 pm

      I have that exact one. Good choice. Gets a little frayed with abrasion because it’s polyester, but it’s airier than the woven nylons.

Leave a Comment