"gutierrezia microcephala" can be toxic to livestock, especially when grown in sandy soil. toxicity is due to the presence of saponins, alkaloids, terpenes, and flavonols, as well as high concentrations of selenium; "g. microcephala" plants have been found to contain selenium levels of 1287 ppm. toxicity symptoms include abortion and death; as little as of fresh "g. microcephala" consumed by cattle in seven days can cause abortions, and in cattle, sheep, and goats consuming ten to twenty percent of their body weight in two weeks can cause death.