بزرگ‌علف

thumb|upright=1.6|Megaherbs on Campbell Island Megaherbs are a group of herbaceous wildflowers growing in the New Zealand Subantarctic Islands and on the other subantarctic islands. They are characterised by their great size, with huge leaves and very large and often unusually coloured flowers, which have evolved as an adaptation to the harsh weather conditions on the islands. They suffer from overgrazing due to introduced mammals.