About Senna armata (S.Watson) H.S.Irwin & Barneby
Senna armata is a species of flowering plant in the legume family. It has two common names: spiny senna and desert senna. This plant is native to desert regions around the intersection of Nevada, Arizona, eastern California, and northern Baja California. It grows in sandy and rocky habitats such as arroyos. It is a shrub that can grow up to one meter tall. It has grooved, branching stems that often narrow into thorns at their tips. The spiny branches are covered in tubular hairs that help protect the plant from hot desert air. Its spine-tipped leaves are each composed of two to four pairs of small leaflets. Leaves of this species are ephemeral, dropping off shortly after emerging, so the shrub is bare for most of the year. Flowers grow singly or in small clusters in leaf axils. They are fragrant and showy, with five petals in shades ranging from yellow to salmon pink. Each flower measures roughly one centimeter long. The fruit produced by Senna armata is a legume pod that can reach up to four centimeters in length.
