Hyotannuma

Once shaped like a gourd, which gave it its name, though the outline has blurred as the swamp slowly transitions toward wetland and forest. The water is shallow and clear enough to see the decomposing leaf matter on the bottom, and you can watch the process of ecological succession playing out around you: sedge and bulrush already advancing on one side, reeds filling in the far end, and the whole system slowly building toward the Japanese horse chestnut and beech forest that will eventually replace it. In spring and summer, forest green tree frogs lay egg clusters in the overhanging branches, and tadpoles drop directly into the water when they hatch.