Wheat fields occupy more of the earth's surface than do fields of any other food crop.
Stem rust is one of the most important wheat diseases limiting production in many areas of the world. The disease has been important throughout the ages. The Romans, in order to please the rust god, Robigus, held a festival called Robigalia. The common barberry was brought to North America by early settlers from Europe, where it had been widely grown for medicinal purposes. The medicinal uses were important enough that barberries were planted in monastery gardens throughout southern Europe.