gutierrezia microcephala is a species of flowering plant in the daisy family known by the common names sticky snakeweed, threadleaf snakeweed, threadleaf broomweed, and smallhead snakeweed. it is a subshrub native to the southwestern united states and northern mexico, and can be found in arid grassland and desert sand dune habitats. it can be toxic to livestock in large quantities, due to the presence of saponins and high concentrations of selenium.