Colutea arborescens aka Bladder Senna

Colutea arborescens, also known as bladder-senna, is a deciduous shrub that can grow up to 12 feet high and has a bushy habit with copious branching. The plant is native to Europe and North Africa, but it can also be found on other continents where it is grown as an ornamental and used in landscaping for erosion control. The leaves of C. arborescens are 3 to 6 inches long, with nine to thirteen elliptic or broadly obovate leaflets that are hairy beneath when young, but become nearly or quite glabrous with age. The plant blooms pea-shaped, yellow flowers that are about 3/4 inch long on a downy stalk that is 1/4 to 1/2 inch long. The flowers are carried in racemes that are axillary on the current season's growth, with three to seven flowers towards the end. The wing-petals are shorter than the keel, and the calyx is cup-shaped with triangular lobes. The inflated and bladder-like pod of C. arborescens is about 3 inches long, 1 to 1 1/2 inches wide, and pointed, containing many seeds. This plant prefers full sun and can tolerate a range of soil types. It is quite aggressive and is considered weedy in some areas.