About Argyroxiphium grayanum (Hillebr.) O.Deg.
Argyroxiphium grayanum is a perennial plant that is endemic to the island of Maui, Hawaii. It typically grows as an erect low shrub reaching up to 2 meters in height, with an erect single-stemmed monocarpic rosette growth form. Plants growing within the interior of bogs, however, usually form dwarf shrubs that are less than 30 cm high. It has green, narrowly elliptic-ligulate leaves with 5–11 nerves, which are widest above their middle point. This species grows only in and around montane cloud forest bogs, at elevations ranging from approximately 1,200 to 2,050 meters. Its growing sites receive between about 300 cm and over 1,000 cm of precipitation each year. It is most abundant along the upper rim of Kīpahulu Valley on East Maui, and near the summit of Puʻu Kukui on West Maui. The Puʻu Kukui region is also home to a related species, the ʻEke silversword (Argyroxiphium caliginis). Even though the two species are closely related and share the same habitat, they differ in several characteristics beyond the color of their lance-shaped leaves: silverswords have a distinctive sheen that A. grayanum lacks. Most species in the genus Argyroxiphium produce just one inflorescence, and die after this event. Neither A. grayanum nor the sympatric ʻEke silversword A. caliginis follow this pattern strictly. Both species flower less often than the mass flowering events of the Haleakala silversword, and produce multiple branches, meaning only some rosettes from an individual plant die back in any single year. In addition, A. caliginis reproduces via runners or prostrate stems that root and spread to form new growth.
