Both are dominated by woody plants. Swamps have wet soil throughout the growing season, but may dry up in the summer. You can find swamps along streams, floodplains, in flat uplands or shallow lake basins. Vernal pools are small bodies of standing water that form in the spring from melting snow or spring rains, and are often dry by mid-summer. Many vernal ponds occur in depressions in agricultural areas, but may also be found in woodlots or bottomland forests.
Vernal pools have vegetation which changes along with the shifting water levels.
Wet meadows look like a fallow or grassy field - except that they are dominated by hydrophytic grasses and sedges. Vegetative cover dominates wet meadows so that there is little or no open water. What little open water exists will evaporate by the end of the spring growing season. Wet meadows often form a transition zone between aquatic communities and uplands with saturated and mucky soils. Any place where you've seen or heard frogs breeding is a good place to monitor.