Baselayers, I’ve written many words on the subject, including these and these. Fancy underwear may be a prosaic subject, but given that you wear it more often than anything else while In The Woods, it is worth both more words and perhaps, more money. Because exciting things are happening.
The orthodoxy of baselayers has for decades been that midweight stuff is around 150 grams/meter (fabric weight), heavyweight 200, and lightweight 120. Merino mixed this up a bit, because 120 weight pure merino doesn’t hold up to abrasion, and thus lightweight merino for standard bearers like Smartwool and Icebreaker is 150. This led to amusing chatter about how lightweight merino was so much warmer than polyester, at least until it gets soaked, and you lack the metabolic force or atmospheric conditions to dry it in a reasonable time frame. Light baselayer fabrics have always been, for me, the best. They dry fastest, from both internal and external moisture, and while this can lead to accelerated evaporative cooling, I prefer to have the luxury of choosing when and how I manage that problem.
Golite and Mountain Hardwear have both offered sub-100 gram/meter baselayers in the past, but they suffered from either spotty availability, or only came in runner-specific designs which were less than ideal for the pack carry-ers. The old standards began to move with the introduction of Capilene 4, a heavyweight baselayer which was almost as light as the “lightweight” Capilene 2 of the time. Cap 4 functioned by creating more dead air space against the skin with less fabric, and has proven to be exceptionally effective and to have good longevity. For temps under 40F it is the fabric of reference, and aside from the eventual poly funk (much reduced, but not eliminated, by treatments like Polygiene) is a rare, faultless, A+ piece of gear.
The standards of baselayer weight are, right now, being permanently reset. In the photo above Capilene 4 is the purple fabric at top left. The camo fabric at top center is First Lite’s forthcoming Aerowool (more below), at right is the hood (top) and body of Sitka’s Core LW hoody, and bottom left is Patagonia’s new Capilene Lightweight. All garments are inside-out. Cap LW is 80 grams/meter, and while Sitka does not advertise the exact specs, their Core LW fabric is comparable. A longsleeved crew neck in Capilene Lightweight weighs 3.5 ounces, roughly 50% less (duh) than the old Capilene 2.
Wicking performance and dry times are proportionally fast. Even late-90s lightweight Capilene was no slouch in these areas, and between the light weight and grid structure against the skin the new stuff is phenomenal. Any garment can be soaked by sweat, but even in cold, humid conditions it takes some pretty silly choices inouter layers to overwhelm something like the Cap or Core LW. Under a breathable, versatile shell like the Black Diamond Alpine Start hoody (as pictured at top) and the range of comfort is impressive. The Sitka hoody, camo and all, has become a favorite because for me it finally fulfills the promise that a hooded baselayer and windshirt could, on their own and with no other accessories, provide for comfort over a 70-90F temperature range. Even the lightest of the old baselayers hoodies, like the Rab Meco 165, never did this for me, while the heavier ones (i.e Ibex Indie) were horrid moisture magnets. Yes the Sitka hoody is 100 dollars, and yes it only comes in camo, but if moisture management is for you an obsession it is one of the best pieces of clothing currently on the market.
Which leaves us with wool. I’ve had a problematic relationships with merino, due as mentioned to issues having something light enough for quick drying, and heavy enough for durability. Meco 120 does this pretty well, but one wishes it were tougher, and captured a little more of a luxurious coziness of wool. Kuiu’s NuYarn 125 is delightfully wool-y, and more durable than pure 120 gram merino, but thus far is still a bit fragile. First Lite’s Aerowool is a ~145 gram/meter 65/35 merino/poly blend, which as First Lite founder Kenton Carruth explained to me differs from Meco in using finer wool, and being a more rigorously uniform blended weave. The result, based on the sample shirt and boxers Kenton sent me, is impressive. You’d never suspect, based on feel, that the fabric is anything other than 100% merino, and yet it dries impressively fast, for any fabric of that weight. They only had a large shirt, which has been hard to love (too big), but the Dobson boxer shorts are outstanding both due to fabric and to the cut, which is more anatomic and plumber’s crack resistance than any pair of undies I’ve ever worn. (See their 2016 catalog here.) For me Aerowool won’t be a summer fabric, but it’s been great in the winter, and should help drive “traditional” outdoor companies to raise their wool game. It is a good, and comfortable, time to be a wearer of fancy undies.