Abstract
We examined the response to the aboveground removal of a noxious invasive plant Rudbeckia laciniata L. (Compositae), conducted in June. The belowground size and proportion of flowering individuals were compared in a plot subject to aboveground removal and in an undisturbed plot in Hakone, Central Japan. The relationship between the number of flowers and belowground size was examined in another undisturbed plot. Although aboveground removal significantly suppressed the flowering rate, the R. laciniata in the aboveground removal plot had a larger belowground size than in the undisturbed plot. The number of flowers increased with the belowground size in the undisturbed plot. Our result indicates that annual aboveground removal conducted in June is not efficient for eliminating R. laciniata; indeed, it may induce mass flowering and seed production when the aboveground removal ceases.
