Native North American Edible Plants
Elderberry, genus Sambucus
The elderberry is another globetrotter (not found exclusively in North America), but one of the neat things about them is that there are five varieties in the US alone. The black elderberry (Sambucus nigra), the one from Europe, was important medicinally for hundreds of years. It was also responsible for a delicious fermented cordial that, when mixed with other good stuffs, was the cough syrup of the world before industrialization. The alcoholic part of that was the joke in Monty Python and the Holy Grail (“Your mother was a hamster and your father smelt of elderberries!”).
The elderberry tree was also the source wood for the elder want, is the wood of choice for some lesser known woodwind instruments, and has a root system that helps foster mycelial activity more than just about any other plant. It was often planted in the middle of the garden so that everything around it could benefit from the soil critters it fostered. Also, the flowers are said to make a lovely tea.
However, beware that only a few types of elderberries are edible raw. Otherwise, you have to cook or ferment them for them to be edible without making you sick.
Pictured is the black elderberry.