Mowing, done properly, is a straight-line art. B.C. Mowing keeps to it — sharp blades, even passes, corners squared, trimmer work wherever the deck cannot reach. From the trail up Memmen Ridge you get the whole grid of Castle Rock at once, a mosaic of green rectangles held against dry high-plains hills. Every one of them is somebody's small win over the altitude and the sun. Adding a few tidy squares to that view each week is a good way to spend a summer, and it looks like something.