macrocephalum, commonly known as the Pu'u 'Alaea greensword is a hybrid species of silversword plant in the family Asteraceae, and is a part of the silversword alliance.

It is endemic to East Maui, primarily near the town of Pu’u Alaea (from which it was named), where it is seen growing beside other Argyroxiphium species.

The population of the hybrid species is unknown, but is likely under threat of feral goats, and pigs that plague silversword plants.

[1][2] The Pu'u 'Alaea greensword is morphologically similar to Argyroxiphium sandwicense subsp.

Pu'u 'Alaea greensword leaves are less hairy, and as a result, are greener than the non-hybrid species.