The Haleakala silver sword (Argyroxiphium sandwicense subsp. macrophages) is part of the family Asteraceae.    From Wordnik.com.  [WN.com - Articles related to BP inks deal to save turtles from oil spill] Reference

A unique feature of many tropical examples of this biome is the presence of giant rosette vegetation belonging to the plant families Lobelia (Africa), Puya (South America), Cyathea (New Guinea), and Argyroxiphium (Hawaii) (Figure 7k-16).    From Wordnik.com.  [Terrestrial biome] Reference