Indigo Bush (Psorothamnus arborescens var. minutifolius)

(Fig. 01)

Picture Notes: While on a trip to Reno, Nevada  back on 05/03/2011, I found several of these beautiful bushes scattered at various locations along Route 95. This rather large one (Figs. 01 & 02) so caught my eye, that I had to slow down and turn around to go back to its location so I could capture a few shots.

Description: Indigo Bush (Psorothamnus arborescens var. minutifolius) can be found growing on dry hills and in desert valley flats between 500 to 4000 feet in elevation, yet mostly in Creosote Bush scrub in the northern and central Mojave Desert. As there are several varieties of this species which are generally similar in appearance; the common name Indigo Bush can refer to plants in any of several genera in the legume family. These are generally a thorny, thickly branched, strongly scented bush. This spreading, somewhat spiny, finely branched small shrub can grow to around 2-5 feet tall and spread to 3-6 feet wide. The pinnately divided leaves have 5-7 lanceolate leaflets that are 1/4-1/2 inches long.  The inflorescence is a long raceme of many flowers with reddish green calyces of sepals and bright purple pealike corollas up to a centimeter long. The flowers are an intense deep violet-blue produced in dense clusters at the branch tips, followed by 2-seeded, gland-dotted fruits that narrow to a long beak. The flowering season is between April and May.

(Fig. 02)