Erodium is a genus of 130 or so species.  Its distribution is based around the Mediterranean Sea but extends across Asia to China and also has representatives in Australia, South America and North America. This site explores the genus Erodium and its sister genus California, from the family Geraniaceae, focusing mainly on the species but also looking at some of the cultivars.

All 132 species have at least a brief description; many have a full description, with photos or illustrations where possible, including distribution, and notes on distinguishing between species. Over time more material will be added.