ON a sunny early November afternoon in the Japanese city of Kanazawa, the alchemy of autumn had already begun transforming the city’s beloved Kenrokuen Garden from an oasis of leafy greens into a gold-tinged sanctuary. Workers were busy constructing yukitsuri — thick ropes tied to fragile tree branches, intended to brace them against heavy snowfalls — in dramatic pyramids that soar over the gnarled wood. And the transformation continues as the seasons progress.