Genus Chorispora Mustard Family (Brassicaceae/Cruciferae)
Most species in the mustard family have yellow or white blossoms,
but this one has small purple flowers.
The blossoms are very tiny (about 1/4 inch across), with four petals
and four sepals -- the pattern of a typical mustard. The plant is
usually less than a foot tall.
The plant is a native of
the high deserts of southern Russia, in southwestern Asia. It is very
drought tolerant, so it has spread rapidly here in this similar climate.
I have seen thick patches of this, forming a purple blanket along
the roadsides in the spring. It blooms at about the same time,
and is the same color as Storksbill (Erodium).
The two plants and their blossoms really do not look at all alike,
but because of the similar color and the small blossom size, they
need to be examined closely in order to see the difference.
It has an unpleasant odor. If eaten by dairy cattle, it will give
the milk a disagreeable taste.