Australia is also affected by the introduction of "Prosopis" spp., in particular, the "P. pallida", "P. glandulosa", "P. velutina," and their hybrid "P. juliflora". "Prosopis" spp. are ranked nationally as one of the 20 most significant weeds. They now cover almost 1 million hectares of land. "Prosopis" spp. were originally introduced to help with erosion because of their deep root systems. They also have immediate uses to humans through timber and providing a food source through their pods. Since Australia is a hot and semiarid region, "Prosopis" spp. have been able to become naturalized.