Fog sits on the river below Palisades most mornings in early summer, and it burns off from the cliff edge downward, so the hamlet's lawns dry first. WILBERCO LLC starts up there and works its way through Orangetown — mowing, edging, keeping beds and borders in shape from the wooded lanes near the observatory down toward Sparkill. Cliff-top ground is thin and rooty and asks for a careful blade. The payoff is a stretch of held green against all that wild gray stone and old forest. Quiet work, in a quiet place, done again every week.