Semi-desert. Sand and rock openings. Spring.
Canyonlands National Park, Utah, May 20, 2004.

This perennial grows from woody underground stock and spreads over several square feet in a zig-zag pattern caused by the lack of growth in the terminal stem bud; side buds grow stems into a sprawling web.  Leaves vary from oval to spade-shaped.

Semi-desert. Sand and rock openings. Spring.
Corona Arch Trail, Utah, April 13, 2005.

What appears to be a flower in the Chamaesyce genus

is instead a cyathium, a cup-like structure (the maroon structure shown in profile in the upper right of the photograph above) that houses a central pistillate flower surrounded by several staminate flowers.  The white scalloped structures are not true petals but merely extensions of the cyathium. 

When fertilized, the central pistillate flower elongates, swells, and hangs out of the cyathium.

Semi-desert. Sand and rock openings. Summer, fall.
Bisti/De-Na-Zin Wilderness Area, New Mexico, October 9, 2007.

Chamaesyce glyptosperma sprawls in an interlaced pattern from a single stem that emanates from a strong taproot.  You can see that all stems in the photograph at left are branching off a main stem which is  just out of sight at top center.  The plant is found in all Four Corners states but we do not have a record for it in Colorado near the Four Corners.

Semi-desert. Sand and rock openings. Summer, fall.
Bisti/De-Na-Zin Wilderness Area, New Mexico, October 9, 2007.

Plants flower for several months and in the photograph at left you can see new flowers (rimmed in white) nestled near the swelling maroon seed pods.  Notice the difference in leaf shape between this Chamaesyce glyptosperma and C. fendleri above.  Leaves of C. glyptosperma can be slightly toothed near the tip (as shown here) or entire (smooth-edged).

George Engelmann named this plant Euphorbia glyptosperma from a plant he collected in 1856 near the Platte River in Nebraska.  It was renamed Chamaesyce glyptosperma by John Small in 1903.  "Glyptosperma" is Latin for "carved seed" and alludes to the grooves and ridges apparent on the seeds (not visible).  This is a native species.