On the western edge of Cornwall the land climbs into Black Rock Forest, and the yards below it never quite lie flat — every one has a small rise of its own to be reckoned with. Grassy knoll landscape reckons with them: mowing, trimming, edging and leaf and debris cleanup on ground that asks for a lighter hand on the uphill turn. September mornings come in cool, and the mower throws a little mist off the top of the grass. A knoll cut well looks like a green shoulder in the afternoon light — even, unscalped, holding its color. Small hills, done right, are the pleasure of this job.