I suggest getting wool pants, the surplus ones that aren't very thick and using one layer of long underware. Don't get the thick surplus ones, I only use those when there is a foot of snow or more or very cold.
Use the lighter wool with underware, take off the underware when it warms. This can be a pain, but ususally can find a good place to do this, like on a rock so your soxs don't get dirty or wet.