"gutierrezia microcephala", a native north american plant, is found throughout the southwestern united states (from california east as far as texas and colorado) and northern mexico (from baja california to tamaulipas, veracruz, and zacatecas). it occurs in a variety of ecoregions, such as arid grasslands, chaparral, sand dunes, and oak or oak-pine woodlands. "g. microcephala" is primarily found in well-drained sandy, gravelly, or rocky soils, and is often found in intermittently dry creeks or on the adjacent slopes. it often predominates on shallow, rocky soil, where grasses are not well established.