With wool it is the weight and bulk. If I have to carry it on my back I tend towards synthetics. I often say, “Synthetics for the trail, wool for the cabin”. On day hikes I love wool for the old timey feel. I have had good luck finding military pants in thin wool and some heavy civy wool pants; shirts too, I pick up Woolrich wool dress shirts and combine them with the thicker military wool shirts. I’d really like to try out a wool baselayer but I have not found cheap ones around here.

The gentlemen who live in the Canadian snow disagree with you:
http://www.wintertrekking.com/community/index.php?topic=2383.0

🙂

Again, this is for the cold dry conditions of Colorado and not the comparably wetter New York.

Every tool has a place and time.

Lastly, it is not “fibers sticking to you” the firemen and military are worried about, it is MELTING ON YOU.
“Synthetic Clothes Off Limits to Marines Outside Bases in Iraq”
http://www.defense.gov/News/NewsArticle.aspx?ID=15478

Eek!

From what I have seen, the US military has gone fully synthetic. Modern synthetics do not stick to the skin when exposed to fire-they just contract. The issue of synthetic materials melting is a concern that emerged with early synthetics, that has been resolved since then. Millions of outdoorsmen use synthetic clothing around fires, including me, without any problem (and so do virtually all firemen).

I also find the claims (from personal experience and testing) about wool staying warmer when damp that fleece to not be exactly true. Wool feels more comfortable under such conditions, but I find it loses just as much heat. The slower drying time of wool spreads out the cooling process, so it might feels warmer than the faster drying fleece in the short term. Overall though, similar amounts of heat are lost.

There are three reasons why I stopped using wool in winter.

The first one you mentioned-very slow drying time. I’ve had instances where I’ve gotten my pants wet on day one of the trip, and they were still not dry on day three. It’s a big problem for me in winter.

The second issue is that it is a snow magnet. Without some type of shell layer, by mid day I look like a snowman. The snow then melts and gets into the fabric.

Most importantly, for me being in the woods in winter is no different from any other season. I do not limit my mobility just because it is winter. As a result, the bulk and extra weight of wool clothing is a major problem. When compared to fill based insulation it is significantly outperformed in terms of insulation per weight.

I heard the US military is getting away from synthetic base layers just for the last reason you stated. :O

Firstly, stink. When you say “can get a pungent odour” you aren’t joking. The older I’ve got, the less tolerant I’ve become of my own and other people’s body odour. Just half a day to unbearable with capilene set against four days to noticeable with merino. I’ll admit to wearing synthetic mid-layers outside winter for the superior wicking.

The other issue is what happens in a fire. I’ll never forget getting into a Sea King helicopter and seeing a notice which said synthetic clothing was not permitted because it fuses with the skin when set on fire. If you do anything bushcrafty, I’d advise sticking to natural fibres. My dad was a fireman and his tunic and trousers were made from thick wool.