On a worldwide basis, oxalate poisoning of grazing animals is usually associated with plants of the wood-sorrel family. This family consists of about ten genera and over 50 species widely distributed in temperate and tropical regions. In North America, oxalate poisoning has been associated with certain members of the chenopod or goosefoot family. The spread of halogeton from the state of Nevada and other states of the Intermountain Area produced several spectacular poisonings of large numbers of sheep. Oxalate poisoning in livestock is of great importance in the Intermountain area. Poisoning occurs primarily from the ingestion of the oxalate-containing plants, halogeton and greasewood. Greasewood is usually found growing on saline/alkaline soils on lake plains from the margins of playas outward toward the surrounding mountains until the ground water table is sufficiently deep that surface wetting does not reach the ground water level at any season of the year.