Phenology of inflorescence development in pohutukawa (Metrosideros excelsa, Myrtaceae)

The development of compound inflorescences in Metrosideros excelsa over a 1 0-week period is described. We identify six developmental key stages from d ormancy to bud break according to morphological characteristics and present a time course of inflorescence development. Vegetative and compound inflor escence buds are initially morphologically identical, with several bud scal es and a spheroidal shape (stage I). Allometric changes result in ellipsoid al buds for approximately eight days (stage II). Deciduous bracts subtendin g the secondary inflorescence axes partly cover cymose inflorescence buds a t stage III. These bracts abscise by stage IV. A pair of bracts and two pai rs of bracteoles, subtending lateral flower buds in each cymose inflorescen ce, become visible at stage V. After all bracts and bracteoles have abscise d, individual flower buds appear clearly separated and petals become visibl e (stage VI).