Why wearing Merino Wool for Hiking?

Properties of merino wool

What you probably already knew: Merino is a wool fiber. Wool, unlike synthetics, has a much higher thermal performance. In addition, wool still insulates even when wet. That's ideal when you're sweating or have had a rain shower where you didn't have your rain jacket to hand quickly enough.

Wool fibers have a temperature-regulating property, so that no heat buildup can occur and there is always a comfortable climate on the skin. Because merino is a very fine fiber, the typical scratching of sheep's wool does not occur (also because of the processing of the wool).

Another very positive property of wool is that it does not absorb odors. Thus, the shirt does not stink even after a long, exhausting day of hiking. Once aired briefly and the next day you can continue hiking.

Areas of application of Merino wool:

Meanwhile, wool is no longer used exclusively in baselayers or insulation jackets, sleeping bags or even jackets that are used as a third and thus outer layer are also produced from wool. In sleeping bags, wool - unsurprisingly - comes as a filler. However, the fiber has little advantage over synthetic or down fillings (higher weight, larger pack size). Compared to down, however, wool has a comparable thermal performance.

On the other hand, jackets made of wool, or more precisely loden, are more interesting. Loden is an extremely tightly woven wool fabric (for example, virgin wool). The density of the material leads to the fact that this is much more robust than conventional wool products, which we all know from the stores.

In addition, loden is to a certain extent windproof and water repellent. The wind, similar to the principle with membranes like Gore-Tex, is deflected by the "branched" fibers and directed back outside without ever reaching the skin. Of course, much more sustainable than a Gore-Tex membrane.

An overview of the advantages and disadvantages of wool garments:

More and more hikers are swapping their synthetic or cotton bibs for shirts made from sheep's wool - which are now available from almost all equipment brands. This is not only due to the naturally woolly feel on the skin and the enormous heat output, but also because wool shirts do not smell of sweat as quickly - an advantage that hut guests in particular appreciate.

But the natural material also has disadvantages: Some people find it itchy on the skin, which is why many manufacturers only process the ultra-fine wool from merino sheep. Many hikers also miss the cooling effect of their synthetic shirts - at least during exertion. When it's hot or their pulse rate is high, they end up like the shaggy cloven-hoofed animals - running hot. But textile engineers have recipes for dealing with this, too: they mix wool with synthetic fibers, give it an open-pored structure or a loose weave.

Fazit: Merino Wool Outfits get more and more popular for Hiking

The most important questions and answers about the natural material Merino here:

1. What distinguishes merino wool? It is finer and more crimped than normal wool. Merino shines with a fiber cross-section of only 16-24 microns (micrometers, i.e. one thousandth of a millimeter), normal wool comes to 24-40 microns. For comparison, a human hair has a thickness of 30-50 microns. Because of the extremely thin fibers, merino feels softer and scratches much less.
   
   
2. Why is merino wool so popular? Because merino wool creates a pleasantly warm feeling on the skin: the strongly curled hairs bind a lot of insulating air due to their wave-like structure, and they can also absorb up to a third of their weight in moisture without feeling clammy. Because wool fibers have an antibacterial effect, no annoying odors form - pleasant when resting in a hut.
   
   
3. Why does Merino not smell? Sweat itself does not smell, but forms the breeding ground for odor-forming skin bacteria. However, they can hold on to the scaly, roof tile-like surface of merino wool more poorly than on smooth synthetic fibers. In addition, the bacteria are broken down by the wool protein keratin. That's why natural fibers don't smell even after many days in use - unlike synthetic shirts.
   
   
4. How well does wool condition the body? Those who hardly ever sweat on tour benefit from wool, as it ensures a dry and warm skin climate. Outdoorsmen, on the other hand, who are quickly in their own juice when their pulse rate is high, have to slow down their pace early on in wool clothing so as not to overheat. They do better with a synthetic shirt or those made of a wool-synthetic or wool-silk blend. Merino shirts with a fine-rib or mesh structure are an exception: they only partially cover the skin and leave zones for perspiration to evaporate, which leads to the desired cooling effect. But such shirts are rare: Among the pure wool models, only the Devold Tuvegga Sport and the Devold Hiking Shirt were able to achieve noticeable cooling effects in outdoor tests.
   
   
5. Can merino scratch? The finer the wool, the lower the risk that it will "bizzle" or even itch on the skin - our experience also shows this. The ultra-thin hairs bend when they press against the skin, adapting to it - unlike thicker and stiffer fibers. Even though the average sensitivity threshold is around 25 microns, wool-sensitive hikers should rather only try on clothes with fiber thicknesses of less than 19 microns - and wash them once before the first wear to rinse out loose fiber residues. Shirts made from a wool blend are a scratch-free alternative. Especially the addition of viscose (Tencell, Lyocell, Modal), but also polyester parts lead to a particularly soft skin feel.
   
   
6. What helps against potholes? Unfortunately, the keratin contained in wool is also tasty to moths. What the beasts don't like, on the other hand, are the essential oils that emanate from stone pine or cedar wood. Lavender (in scented sachets) is also suitable as a defense - simply place it in the closet. If the laundry is stored there for a longer period of time - e.g. during the summer - it should be washed beforehand in order to rinse out skin oils and residues, as moths are also attracted to these. Regular airing of the closet is also helpful.
   
   
7. What is the measure of quality? Good wool is precious - and has its price. The cheaper the shirt, the closer you should look at the label and the manufacturer's homepage: Is the shirt made of pure merino wool (100%)? How fine are the fibers? Where was the item produced? Particularly high-quality goods often come from Europe, especially Germany, Sweden, Austria and the Baltic States.
   
   
8. How do you wash merino wool? Even though many manufacturers recommend hand washing, merino shirts can also tolerate a machine wash cycle - on the "wool" or "delicates" setting. The recommended detergents are those that do not contain protease (such as Aclima "Wool Shampoo"). This enzyme attacks the protein molecule keratin contained in the wool and can change the surface structure. In addition, merino clothing should not be washed together with jeans, raincoat and co: Zippers and metal buttons can tear holes in the delicate knit - unless the wool items are in a laundry net. After the wash cycle, do not spin the items or put them in the dryer, but rather spread them out flat on a laundry rack and later - when they are still slightly damp - pull them into shape a bit. To increase the life span and to avoid holes, Merino should be washed only rarely (and if, then as described above). Especially since due to the self-cleaning function of the fibers, an overnight airing is completely sufficient.
   
   
9. How well are the sheep doing? Mulesing is the main source of criticism. In this process, large skin folds on the lambs' buttocks are cut off without anesthesia to prevent fly larvae from settling in them. Sheep are also repeatedly injured during shearing, which often takes place on a piecework basis, as research by animal protection organizations has shown (see: peta.de/wool). Other problem areas include the use of insecticides, improper slaughter and the mass live export of sheep to Middle Eastern countries and Africa. Fortunately, however, more and more outdoor manufacturers are concerned about animal welfare and have farms and suppliers regularly inspected and certified by independent organizations.
   
   
10. How sustainable is merino? As a renewable natural product, wool does not require the use of petrochemicals. Merino also sheds no microplastics, needs to be washed much less frequently than synthetic clothing, and lasts a very long time when properly cared for. The natural fibers also decompose, but can also be recycled. Last but not least, sheep - with ecologically oriented pasture management - contribute to the preservation of the cultural landscape. On the other hand, there is a very high climate impact, not only due to long transport routes, but also due to the ruminants themselves (CO₂ and methane), and in conventional husbandry also the use of pesticides. However, if you wear your merino clothing for as long as it lasts, care for it properly and wash it infrequently, at least the carbon footprint looks better.