Locoweed (also crazyweed and loco)'s a common name in North America for any plant that produces swainsonine, a phytotoxin harmful to livestock. Worldwide, swainsonine's produced by a small number of species, most in three genera of the flowering plant family Fabaceae: Oxytropis and Astragalus in North America, swainsonine toxicosis, locoweed disease, and loco disease; North America) and pea struck (Australia). Locoism's reported most often in cattle, sheep, and horses, but has been reported als… (More on Locoweed)