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Granivorous heteromyid rodent species and Indian ricegrass (Achnatherum hymenoides), a perennial grass common on sandy soils, are both widely distributed throughout North American deserts. Previous research demonstrated that the vast majority (~95%) of Indian ricegrass seedling recruitment occurs from seed clusters cached in shallowly-buried scatterhoards by heteromyids, especially Merriam�s kangaroo rat (Dipodomys merriami). Here, we discuss how emergence of seedlings in aggregated clusters from caches affects subsequent seedling survival and establishment. In two western Nevada field studies, we monitored single Indian ricegrass seedlings and clumped seedlings in caches over the course of a year. Individual seedlings within clumps generally had higher survival rates than seedlings growing singly, and whole caches routinely had higher survival than single seedlings. We followed these observational studies with a field experiment in which Indian ricegrass seedlings were transplanted inside fenced plots either singly or in clumps of 25 or 35 seedlings and survival was compared through their first winter. Individual seedlings within clumps had higher survival than seedlings growing singly, and seedlings within clumps of 35 generally had maximum survival. These results suggest a mutualism involving heteromyid rodents and Indian ricegrass. Indian ricegrass seeds provide a highly preferred food resource to heteromyids, while benefits to Indian ricegrass extend beyond seed dispersal and seedling emergence into the longer-term survival of the plant. Finally, by broadcast seeding commercial seeds (millet) as an alternate resource for rodents, we tested whether such �diversionary seeds� can enhance seedling recruitment resulting from Indian ricegrass seeds that had been cached by rodents by reducing numbers of these caches that rodents recover for consumption. Seedling recruitment was greater where diversionary seeds were applied, indicating that this mutualism can be applied in an arid-land restoration context.