Gutierrezia microcephala and its variant Gutierrezia texana var. glutinosa are known as sticky snakeweed.
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 Mojave Desert as well as other areas of the southwestern United States and northern Mexico, and can be found in arid grassland, desert sand dune, chaparral, and oak or oak-pine woodlands at altitudes up to 7,500 feet, where there is well-drained sandy, gravelly, or rocky soils, and occasionally in dry creeks or on slopes adjacent to dry creeks. It will predominate on shallow, rocky soil, where grasses are not well established.
Gutierrezia microcephala is a small, resinous, perennial desert subshrub in the Asteraceae (sunflower) family that is typically eight inches to 24 inches in height and less than 40 inches in diameter. It is heavily branched, giving it a spherical shape. Its shoots and twigs are green to yellow in color, which upon aging become brown and woody. The leaves are linear, threadlike, and alternate; two-fifths of an inch to 1.6 inches long and one-fifth inch to four-fifths of an inch wide. Not just the leaves but the stem tissue is photosynthetic, giving the plant an uncommonly high photosynthetic capacity. Sticky snakeweed typically flowers from July to October, depending on the amount of rain.
Gutierrezia microcephala manifest sessile inflorescences of 5 or 6 flowers at the tips of the branch stems.
The yellow flower buds, which originate as waxy knobs, open into golden yellow flower heads, each of which has one or two disc florets between one-twelfth of an inch to four-fifths of an inch to one-eighth of an inch in diameter, and one or two ray florets between one-twelfth of an inch to one-seventh of an inch in diameter. The mature plants prolifically produce seeds, but because the plant features a very small puppus which renders wind-borne seed distribution very inefficient, the majority of seeds fall within three to seven feet from the parent plant.
Gutierrezia microcephala was used by the Native Americans for medicinal and other purposes. The Cahuilla mixed it with water to create a gargle or placed the plant directly in their mouths to alleviate toothaches. The Hopi and Tewa used the plant as a carminative, as prayer stick decorations, and for roasting sweet corn, The Navajo applied a poultice of the plant to the back and legs of horses. The Zuni boiled the flower heads to brew a tea used as a diuretic, tonic, and sweat-inducer, and relied upon the plant as a water indicator.
Though sticky snakeweed is of little known use to wild or domesticated animals, when other forage is unavailable, livestock and wild ruminants will feed upon it. This can prove unfortunate for those animals if it is consumed in any quantity, as it contains aponins, alkaloids, terpenes, and flavonols, as well as high concentrations of selenium, in some cases as many as 1,287 parts per million. Plants growing in sandy soil are particularly toxic. If cattle, sheep or goats consume twenty pounds of gutierrezia microcephalas in seven days, it can cause abortions. Death can result in cattle, sheep, or goats which consume ten to twenty percent of their body weight in gutierrezia microcephalas in two weeks.