Rattlesnake Weed (Euphorbia albomarginata)

(Fig. 01)
Picture Notes: I found a several of these interesting flowers (Figs. 01 & 02) in the middle of a wash on a recent hike through the Wee Thump Joshua Tree Wilderness Area, located just west of Searchlight, Nevada. Why it is referred to as "Rattlesnake Weed" I have no clue. Click here for more information on this location … Wee Thump Joshua Tree Wilderness Area.

Description: Euphorbia albomarginata, common names Rattlesnake Weed and Whitemargin Sandmat, is a small low-growing annual native to desert, chaparral, and grassland habitats of from southern and central California to Northern Mexico and Louisiana. It can be easily identified by its small size, dusty green leaves, very flattened growth pattern, and the white circular margin around the edge of its burgundy centered flowers. This ground cover plant is usually no more than 1/2 inch high, with individual plants growing closely and forming mats of vegetation covering roughly a square foot. The flowers of this plant are tiny and edged in white, with a purplish or burgundy center. The plant actually has no petals, but has modified leaves called (bracts, more round than the green leaves on the rest of the plant, which form a cup-like shape. The 12-30 male flowers are difficult to see, consisting only of one stamen each, and are clustered in the center of the cup. The single female flower is at the center, with an elevated ovary pendant on a long stalk, which when fertilized and mature, bears a capsule fruit. Its leaves are round to heart shaped with the point of the heart away from the small stem attaching the leave to the branch (petiole).
The "non-flower leaves" are a peculiar "dusty green", with green but sometimes with burgundy like edges, and burgundy like stems, similar in color to the flower center inside the white ring, and particularly so after a late Spring or Summer rain. It has a white milky sap, and is poisonous. It can be found in open fields, on roadsides, desert plateaus or anywhere where the ground is disturbed.
(Fig. 02)