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This study was carried out in a research area in the southern Caldenal, a central semi-arid region of Argentina, from which large herbivores are excluded. Samples were collected from the surface litter, 0-4 cm and 4-8 cm deep soil layers. Number of individuals per species in the samples was determined by a combination of seed count and a germination technique. Species diversity per stratum and similarity between strata were calculated. The bulk of the propagules were concentrated in the surface litter and in the top soil layer, with a sharp decrease with depth. Many Medicago minima fruits were found in the surface litter. Seeds from preferred grasses, most of them of the Stipa. genus, were found chiefly in the 0-4 cm soil layer. Except for Larrea divaricata, woody species that are relatively abundant in the plant community were absent. The three strata were very similar; diversity decreased with depth.