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In the last years there has been an increasing number of reports showing failures in the re-seeding of rangelands with native or introduced grasses. This study was conducted to evaluate the germination, survival, and morphological development of seedling rangeland grasses according to seral stages. The study was conducted in germination chamber conditions with sunlight simulation (12 hours-day), temperature (Day 33oC/Night 25oC), and air-humidity (60%). There were evaluated two cycles in three species per each seral stage (early, mid and late). There were used pots filled with sterilized sand soil (123.31 cm3), which were watered daily with deionized water with Hoagland solution.� Each pot was divided into four quadrants, and three seeds were placed in each quadrant. �Daily we evaluated the germination rate and each four days we measured the morphogenesis of 36 seedlings. We repeated the procedure 12 times. In total, we analyzed 432 seedlings for each seral stage. For morphogenesis analyses, the seedlings were washed from the pots with cold water and measured the following variables: Shoot length (mm), number of adventitious roots, the length of seminal and adventitious roots (mm). The data was subjected to analysis of variance and means were compared by Tukey test (P<0.05). On average, less of 4% of late seral species reached juvenile phase; we addressed that failures in the establishment were caused by a low proportion of adventitious roots. Early and late seral species showed a morphological biomass allocation marked by times of more root growth and times of more biomass allocation to the shoot. �In conclusion, germination is not a good indicator of success in the re-seeding; and re-seeding with late seral species is a practice with low chances of success due to a high mortality of seedlings in the juvenal phase.