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Species composition, number of emerging seedlings, species diversity and functional group of the soil seed banks, and the influence of grazing on the similarity between the soil seed banks and aboveground vegetation, were studied in 2008 and 2009 in a semi-arid savanna of Ethiopia. We tested whether the availability of persistent seeds in the soil could drive the transition from a degraded system under heavy grazing to healthy vegetation with ample perennial grasses. A total of 77 species emerged from the soil seed bank samples: 21 annual grasses, 12 perennial grasses, 4 herbaceous legumes, 39 forbs, and 1 woody species. Perennial grass species dominated the lightly grazed sites, whereas the heavily grazed sites were dominated by annual forbs. Heavy grazing reduced the number of seeds that can germinate in the seed bank. Species richness in the seed bank was, however, not affected by grazing. With increasing soil depth, the seed density and its species richness declined. There was a higher similarity in species composition between the soil seed bank and aboveground vegetation at the lightly grazed sites compared with the heavily grazed sites. The mean similarity between the seed banks and aboveground vegetation was relatively low, indicating the effect of heavy grazing. Moreover, seeds of perennial grasses were less abundant in the soil seed banks under heavy grazing. We concluded that restoration of grass and woody species from the soil seed banks in the heavily grazed areas could not be successful in semi-arid savannas of Ethiopia.

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The range condition was assessed in six communal grazing areas and one Government ranch in both areas encroached by bushes or shrubs and non‐encroached areas. In each area, three altitude zones were distinguished and in each altitude zone one transect, covering both encroached and non‐encroached rangeland, away from water sources, was selected. The assessment was based on botanical composition of the herbaceous layer, basal cover, litter cover, relative number of seedlings, age distribution of grasses and soil condition. A total of 41 grasses, four legumes, three sedges and 28 tree and/or shrub species were identified. The grasses Aristida adscensionis, Cenchrus ciliaris, Chrysopogon aucheri and Panicum coloratum were common or dominant in all sampled areas. Pennisetum mezianum and Pennisetum stramineum were typically found in the encroached vegetation. In general, the range condition was good. The encroached vegetation had a significantly lower score for range condition than the non‐encroached vegetation for most of the parameters as well as for the total score, although the differences were small. Differences based on altitude and distance of sample sites from water sources within transects were not significant, except for the relative number of seedlings. No signs of overgrazing were detected.

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