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Long-term demographic studies of individually labeled herbaceous plants facilitate analyses of performance at the site level over successive growing seasons.Nervilia nipponica is a small,terrestrial orchid endemic to the Pacific seaboard of central and southwest Japan and Jeju Island in South Korea,where it tends to form isolated populations that typically comprise tens of emergent shoots at most.It is characterised by a hysteranthous growth habit in which a single,one-flowered inflorescence and a single cordate leaf are produced successively from a giobose subterranean tuber within a single growing season.It exhibits a strong capacity for both annual seed set through autogamy and vegetative propagation through the annual production of lateral runners.The absence of pollinator limitation lends the species to non-invasive studies of trade-offs in alternative reproductive modes.The present study examines yearly fluctuations in the numbers of N.nipponica shoots emerging over a ten-year period at an unusually large population at the centre of the species range.