Great Basin Naturalist


Medusahead is another in the extensive list of annual herbaceous species to invade the temperate desert rangelands of the Great Basin. Medusahead is not preferred by large herbivores and apparently is not preferred by granivores. Herbage of this annual grass enhances ignition and spread of wildfires. Medusahead is highly competitive with the seedlings of native species and is probably the greatest threat to the biodiversity of the natural vegetation that has yet been accidentally introduced into the Great Basin. Despite the obvious biological disruptions that are associated with medusahead invasion, the species offers a wealth of opportunities for students to examine the mechanism by which this species is so successful. Students of evolution, plant physiology, and ecology may find this species to be an excellent model for colonization.