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Seeds (nutlets) of four temperate-zone perennial Carex species from various habitats and with different growth forms were investigated toidentify seasonal germination patterns. In the first experiment, freshly matured seeds were sown in summer 1994 on the soil surface and at a depth of 1 cm at a sun-exposed site and under a leaf canopy in anexperimental garden. In the second experiment, seeds were exhumed after various periods of burial (7-cm depth) for up to 30 months and tested for germination in both light and darkness at 15 deg. , 25 deg. , and 22/10 deg. C. In the first experiment, freshly-matured seeds ofthe four sedges did not germinate during summer or autumn 1994. Almost all surface-sown seeds of the four species germinated from late spring to summer in 1995 at the sun-exposed site. Most buried seeds of three species germinated in the soil, but germinants died prior to emergence. In Carex flacca, however, about 50 % of the buried seeds germinated and emerged until 1997, and the ungerminated seeds remained viable. At the shaded site, seeds of C. acutiformis. and C. flacca didnot germinate, whereas a small percentage of the buried and surface-sown seeds of C. arenaria and C. extensa emerged in the second year. Seeds of C. acutiformis and C. flacca were dormant, and those of C. arenaria and C. extensa were conditionally dormant at the beginning ofthe second experiment. All four species had annual dormancy cycles at 22/10 deg. C in light and in darkness and at 25 deg. and 15 deg. in light. Seeds came out of dormancy in late autumn or winter and re-entered dormancy or conditional dormancy in late spring or early summer. Very few seeds of any of the four species germinated at constant temperatures in darkness. No seeds germinated during burial in soil at a depth of 7 cm. These field germination patterns indicate that thefour sedges have the potential to form a persistent seed bank but that losses due to germination in the seed bank are dependent on temperature [ABSTRACT FROM AUTHOR]