Southeast of town, the cottonwood bottoms the old maps call Big Timbers still mark the line of the Arkansas, and on a clear January night the cold there has a glassy stillness to it. Colorado Green Insulation works the snow side of that season in Lamar — plowing, opening driveways and lots, keeping walkways passable when the temperature refuses to climb. Storms here run short and mean; the shoveling is easy and the drifting is not. The measure of a good night is a driveway you can back out of at six in the morning without giving it a thought. Lamar wakes early, and the pavement ought to be ready when it does.