Wandering through the Luxembourg Gardens as the sun was going down on a perfect December afternoon, I was suddenly reminded of a series of Monet's haystack paintings that I had seen many years ago. But what I was seeing weren't haystacks -- they were huge mounds of leaves, golden in the late-afternoon sun, neatly spaced in small fenced-in areas all through the park. I assumed they had been piled up and were eventually going to be carted away, but I later learned that the leaves are left throughout the park to compost and eventually break down into soil. Sounds eminently sensible to me, and it's yet another dimension of this greatest of public spaces in Paris.