There are numerous species of larkspur (Delphinium spp.) in North America. Larkspurs are a major cause of cattle losses on western ranges in the USA, especially on foothill and mountain rangelands. The toxicity of larkspur species is due to various norditerpenoid alkaloids. In this article, we review the current knowledge regarding larkspur ecology and distribution, analytical technologies to study and quantify the toxins in larkspur, the toxicology of the larkspur plants and their individual toxins, known genetic variations in larkspur susceptibility, and current management recommendations to mitigate losses from larkspur poisoning.
