For early season bowhunting, my favorite pants are of soft cotton with a camouflage pattern of no particular brand name. For later season hunting, I use Woolrich wool pants for rifle hunting. and for late season bowhunting, camo pants of "wolfskin" material made by these guys.
http://www.graywolfwoolens.com/store/

They are light and wind and water repellent. I wear them over wool pants.