(yellow tack stem) is a common, spring-blooming wildflower of the Mojave and Sonoran deserts. From the rosette of divided, green, basal leaves, a stout stem rises a foot or more, branching a few times, topped by yellow flower heads supported by green phyllaries. Flowers have one or more rows of toothed petals and thin, yellow-white stamens at the center. Small (tack-shaped) glands along the stems produce a milky sap. Smaller, undivided leaves grow at widely spaced intervals along the stalk.