What sort of socks should I wear for Walking or Hiking?

Ok, so you're really getting into this walking game and you have even ventured into the fantastical realms of hiking.  You even got yourself some snazzy footwear, which is great.  Now you're thinking your normal everyday socks don't quite look the part and aren't quite up to scratch.  Maybe there is a secret.  Maybe there are special socks that will make your walking and or hiking experiences even better.  

Materials: Merino Wool 

Years ago you might see a smattering of cotton and polyester hiking socks on the trails, but merino wool is now the leader far and away. Merino is extremely comfortable, wicks moisture well, and does a nice job of breathing and regulating temperature. It also takes much longer to build up stink, allowing for extra days of wear on a hiking or backpacking trip (how many days is up to you). Cotton, on the other hand, is heavier, absorbs moisture, and doesn't dry when wet. And while polyester may keep you cool, we are yet to find an option that doesn't start stinking rather quickly.
What exactly is merino wool and what makes it so great? Merino is a highly prized type of sheep that lives predominantly in harsh mountain environments, including New Zealand’s Southern Alps. Having to adapt to their tough environment is what gives merino wool its excellent performance characteristics, and the merino variety isn't itchy like wool socks of old. There are a number of merino breeds and the wool strands vary in thickness from ultrafine (17.5 microns and below) to strong (24 microns). 
Even merino wool hiking socks aren’t 100% merino: you’ll notice that the percentage of merino is between 50 and 80%, with the rest being a blend of nylon and spandex. 

Thickness and Insulation

Sock manufactures offer a variety of sock thicknesses designed for everything from summer hiking to mountaineering. For the purposes of this section, we are evaluating overall sock thickness (ultralight, lightweight, midweight, etc.) and not the strands themselves as described above. For three-season hiking, backpacking, and casual wear, we recommend the lightweight versions, which provide solid levels of padding and insulation for temperatures from approximately 40 degrees to 80 degrees Fahrenheit. They also wear well around the house and under your favorite pair of shoes, provided there’s enough room.
If you’re hiking in hot places like Utah or Arizona in lightweight hiking shoes, you may want to consider an ultralight hiking sock. The downside is that ultralight socks are thin on the foot and offer significantly less padding and blister protection than lightweight and midweight socks. Another option for summer hikers is a lightweight hiking sock in a 1/4 height, which has less leg coverage and a more airy feeling but the same cushion on the foot. For winter hiking and mountaineering, the major brands make midweight and heavyweight options that provide much more warmth than the lightweight versions. Keep in mind that these burly socks are overkill for three-season hiking and casual use. In normal temperatures your feet will sweat, and despite merino’s impressive ability to wick moisture, you will get unwanted dampness.

Sock Height

Crew is the most common hiking sock height, which extends 6 to 8 inches above the heel and at a least a couple of inches above just about any pair of hiking boots. We feel that this is the optimal height for hiking: crew socks don’t make you excessively hot and offer some added lower leg protection from brush and rocks. Hiking pants can be quite thin, so the extra cushion is helpful, and particularly if you’re wearing shorts on all but the easiest of trails, crew is the way to go.
Quarter (1/4) height hiking socks cover the heel and ankle but don’t extend up the leg as far as crew socks. Minimalist hikers and those out in the heat of summer may prefer 1/4 socks like the Smartwool PhD Outdoor Ultra Light Mini, which work well so long as you aren’t wearing boots with high ankles (you may end up feeling some friction) and don’t need protection from abrasions. Many mountaineering and ski socks are knee high, which provide the added bonus of warming the lower portion of your leg. 

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