False Indigo (Amorpha Fructiosa)

This shrub, which often forms thickets on riverbanks and islands, can be weedy or invasive in the northeast. Another False Indigo (A. herbacea) has whitish to blue-violet flowers in fan-like masses on top of the plant and gray-downy foliage with up to 40 leaflets. The genus name, from the Greek amorphos (formless or deformed), alludes to the fact that the flower, with only a single petal (the banner or standard), is unlike the typical pea flowers of the family.