Open savanna-like communities dominated by Myoporum sandwicensis and the endemic Sophora chrysophylla (Fabaceae) are principally found on Hawai’i but there are some on East Maui. They occur as an interrupted belt above the montane forests on the high lava and ash slopes. On Hawai’i they are found primarily on Mauna Kea and to a lesser extent on Mauna Loa and Hualalai. Associated trees include the endemic Chamaesyce olowaluana (Euphorbiaceae) and Santalum haleakalae (Santalaceae), although many of the trees are very shrubby. A large proportion of the associated shrub and ground layer species tend to be concentrated under trees particularly Sophora trees where they benefit from ‘fog drip’. These include endemic shrubs like Chenopodium oahuense (Chenopodiaceae), Geranium arboreum (Geraniaceae), endemic herbs like Hesperocnide sandwicensis (Urticaceae), Sanicula sandwicensis (Apiaceae), and suspended from the trees and shrubs can be found the endemic vine Stenogyne microphylla (Lamiaceae).

References

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