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Hawai'i tropical high shrublands
Hawai'i tropical high shrublands
RESOLVE 639
The Hawaiʻi tropical high shrublands occupy the upper slopes of four great volcanoes in the US state of Hawaii: Mauna Kea, Mauna Loa, and Hualālai on Hawaiʻi Island, and Haleakalā on Maui. Above the forest line, alpine deserts and grasslands give way downslope to subalpine shrublands, where hardy, cold- and drought-adapted plants dominate, including ʻāheahea (Chenopodium oahuense), ʻōhelo ʻai (Vaccinium reticulatum), naʻenaʻe and related Dubautia shrubs, and ʻiliahi sandalwood (Santalum haleakalae), alongside tussock grasses such as Deschampsia nubigena. This is a high-elevation subtropical highland climate marked by dry, cold conditions on the exposed summits. Its signature plant is the Hawaiian silversword, ʻāhinahina (Argyroxiphium sandwicense), part of an endemic alliance descended from a North American tarweed, while the nēnē goose and ʻuaʻu (Hawaiian petrel) are among its native fauna. The ecoregion is considered vulnerable, pressured by grazing and trampling from feral livestock and by invasive species. For mountain or rock gardeners, the native ʻōhelo (Vaccinium reticulatum), a low cranberry relative, is a notable cold-hardy ornamental from this flora.
Hawai'i tropical high shrublands location on world map
Marker placed inside the RESOLVE 2017 polygon at 19.5°N, 155.6°W.
Climate snapshot for this ecoregion
USDA zone range (now)
10a-13a
USDA
What seed packets and nursery tags reference. Coldest-day survival semantics.
Plotwright projection (2041–2070)
11b-13b
Plotwright
Where CHELSA models say the typical winter month is heading.
Average warming this ecoregion is on track for: +3.0°F by mid-century. SSP3-7.0 (current trajectory) · CHELSA v2.1 bio06 sampled across 10 of 10 points within this ecoregion's bounding box.
At a glance
Dominant biome
Tropical & Subtropical Grasslands, Savannas & Shrublands
Realm
Oceania
Approximate area
715 sq mi
Conservation tier
Nature Could Recover (Dinerstein NNH 3)
About the tropical & subtropical grasslands, savannas & shrublands biome
Warm grasslands and savannas where grasses dominate and trees are scattered, maintained by seasonal rainfall, grazing, and fire. They support large herbivore communities and respond sharply to wet–dry cycles.
Catalog plants suited to this ecoregion
Computed from each plant's stated USDA zone range against this ecoregion's USDA Plant Hardiness Zone Map 2023 (1991-2020 climatology) via ArcGIS FeatureServer published current zone range, with the CHELSA mid-century warming delta applied for the projection. Plants whose stated range falls outside both the current and projected zone end up dropped; the rest land in one of the three buckets below.
Collections for this ecoregion
No curated collection's plants all fit this ecoregion's zone range. We surface a collection only when every member would grow here — partial fits get filtered out rather than mislead. As the catalog and the curated set both grow, this section will fill in.
Sources
Summary drawn from One Earth, Wikipedia.
Plotwright
Climate-aware plant planning — every plant checked against your zone now and in 2050.
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