Hibiscadelphus giffardianus viscosa"), and naio ("Myoporum sandwicense"). "H. giffardianus" is a small tree, reaching a height of and trunk diameter of . Hibiscadelphus giffardianus Hibiscadelphus giffardianus (Kilauea hau kuahiwi) is a species of flowering plant in the mallow family, Malvaceae, that is endemic to the Big Island of Hawaii. It is believed to be extinct in the wild; any remaining plants are threatened by habitat loss. Cultivated plants exist in Hawaii Volcanoes National Park. It inhabits mixed mesic forests on the slopes of Mauna Loa at elevations of . Associated plants include ōhia lehua ("Metrosideros polymorpha"), koa ("Acacia koa"), mānele ("Sapindus saponaria"),
Hakalau Forest National Wildlife Refuge numerous deep gulches. Rainfall decreases to about at elevations above , where majestic koa ("Acacia koa") and red-blossomed ōhia lehua ("Metrosideros polymorpha") trees form a closed-canopy forest. Further upslope, above , rainfall decreases to or less and native forest merges into abandoned pastureland where alien grasses and weeds, introduced as forage for cattle, are the dominant vegetation. Since 1989, over 400,000 koa, ōhia, and other native plants have been planted in this area as part of the refuge's reforestation program. The Pua Akala Cabin, located within the refuge, was nominated to the National Register of Historic Places in August 2008.