The heaviest snow of a Fort Collins year usually shows up in March, wet as a wrung towel, bending the pear trees and stopping the Harmony Road corridor cold. KORBY LANDSCAPE - FT COLLINS is set up for that kind of storm, the one where a driveway holds eight inches of water disguised as powder. Plows go where plows fit, hand work takes the walks and the steps, and de-icer goes down on the shaded concrete the afternoon sun never reaches. By the time the front breaks and the sky does its usual improbable blue, the lots are open and the walks are safe to cross. That is the whole ambition — a storm that ends earlier for everybody else.