Amorpha canescens

Amorpha canescens, known as leadplant, downy indigo bush, prairie shoestring, or buffalo bellows, is a small, perennial semi-shrub in the pea family (Fabaceae), native to North America. It has very small purple flowers with yellow stamens which are grouped in racemes. Depending on location, the flowers bloom from late June through mid-September. The compound leaves of this plant appear leaden (the reason for the common name "leadplant") due to their dense hairiness. The roots can grow up to 5 m (16 ft) deep and can spread up to 1 metre (3 ft 3 in) radially. This plant can be found growing in well-drained soils of prairies, bluffs, and open woodlands....read more on Wikipedia.