 The Shasta ground sloth is believed to have played an important role in the dispersal of "Yucca brevifolia", or Joshua tree, seeds.Preserved dung belonging to the sloth has been found to contain Joshua tree leaves and seeds, confirming that they fed on the trees.It has been suggested that the lack of Shasta ground sloths helping to disperse the seeds to more favourable climates is causing the trees to suffer.