Native plants are generally considered the best option for plant materials to restore productivity and diversity to degraded rangelands (McArthur 1988). It is difficult to find native plants capable of becoming established from seed in dense stands of introduced annual species such as cheatgrass. It has been easier to import species such as crested wheatgrass to restore perennial grasses on degraded rangelands. Although successful, such revegetation has not been without drawbacks. Establishment of large areas of a single plant species lowers vegetative diversity and may be aesthetically less desirable than a diverse community of native species. Monocultures also tend to have insect and disease problems that are less prevalent in plant communities with greater diversity.