Reproductive biology of Phormium tenax: a honeyeater-pollinated species

Abstract

Phormium tenax, studied on Tiritiri Matangi Island and in Auckland, reproduces asexually by offsets and sexually by large inflorescences. Flowers are protandrous hermaphrodites that exhibit partial dichogamy and herkogamy. The pollen or the stigma are presented sequentially for initial contact with floral visitors. Nectar rewards are greatest during the male phase of flowering. Shape and configuration of flowers ensures that large birds are the most likely pollinators. Two honeyeaters (Meliphagidae), tui Prosthemadera novaeseelandiae and bellbird Anthornis melanura were the most frequent visitors and pollinators although some introduced bird species also commonly visited, especially in Auckland City. Many flowers appear to function solely as pollen donors.