Home Forums Hunting & Shooting Backpack Hunting Thermal bottoms for cold weather

This isn't necessarily a backpack hunting question, but this is the best forum for clothing questions.

So here goes;

I want some base layer cold-weather long underwear bottoms for short walks (1/2 to maybe a mile), but extended sits, that might be 1-3 hours in length. Fall/winter temps in my area run in the 10-40 degree range.

What's the stuff to get that won't burn you up on a short hike, but keep you somewhat comfortable for an extended glassing/sitting situation?

Thanks!