In Spanish, "playa" may mean a beach or a flat open space. It's the latter meaning used in the Chihuahuan Desert to refer to lake beds that hold water only periodically. The reasoning behind this is obvious—the dry lake is indeed a flat, open space. With occasional influxes of water followed by evaporation, salts leached from surrounding highlands accumulate, often to the point that the alternative name of salt flats is applied.
The high level of salts in playas bars most plants. Not so the Iodine
Bush. Spending part of its energy to tuck away the salt in spaces within its cells, it
manages where other plants fear to go. Often, it's the only plant surviving at the
margins of a playa. Fleshy stems produce a brownish liquid when crushed and have a
salty taste—both attributes that have been claimed as a source of its name. Most
animals are repulsed by the taste and unable to handle the excess salt. Good for the
plant, but there is one chink in its defense—unfortunately for it, the seeds are quite
edible.
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.