On the first Tuesday after the hard wind, a single maple leaf reached the storm drain outside a particular brick rowhouse three full days before its neighbors, wedging itself flat against the grate with the confidence of something that had scouted the route in advance. This is not unusual. Gutters routinely host one early leaf while the rest of the canopy is still deciding whether to let go, and that leaf, once seated, tends to stay seated: water pressure from light rain presses it tighter against the grate rather than washing it through, and only a heavier flow, or a boot, dislodges it.
Species matters less than shape. Broad, flat leaves, maple and sycamore especially, form a better seal than narrow ones and are more likely to be the specimen still visible weeks later, bleached pale by sun and repeated wetting until its veins stand out like something pressed in a book. Oak leaves, being stiffer, tend to skitter past the grate entirely and collect instead against curbs and fence bottoms, a different specimen with different habits. The gutter leaf's decline is slow and visible: green to brown to a kind of tea-colored translucence, the color leaving before the shape does. City crews clear the obvious pileups but rarely chase the single holdout, leaving it pressed against the same six inches of grate long after the ones that arrived later have washed through.