wetland species
There are several good choices, depending on your zone. The following are just a few:
acer negundo - yuck, the box elder
acer rubrum - lots of good red maples out there
acer saccharinum- silver maple
betula nigra- river birch
fraxinus pennsylvanica- green ash
Liquidambar sturaciflua- sweetgum, real nice but need an acid soil
liriodendron-tulip tree, these get huge
nyssa- black tupelo, good fall color, transplant young
platunus- London planetree
Quercus palustris- Pin oak, acid soil preferred
Salix- willows, some are quite messy
taxodium- Baldcypress, a deciduous conifer
For shrubs or small trees you might investigate-latin only
Aronia
Clethra
Cornus
Ilex
Lindera
Rhododendron
Salix
Styrax
Zenobia
Good luck!