`Ohi`a Lehua (Metrosideros macropus)

Flower of Metrosideros macropus. Photo Credit: Matthew Garma

Global Rank: G2 - Imperiled
Legal Status: N/A
Family: Myrtaceae
State: HI
Nature Serve ID: 152290
Lifeform: Tree
Date Inducted in National Collection: 10/25/2019

Description:

Metrosideros macropus (ʻŌhiʻa) is a small tree (5-7 m) endemic to O'ahu. It is distinguished from other local species by the long-persistent inflorescence bracts and wider leaves. Flowers are mostly yellow, but are occasionally red.

Where is `Ohi`a Lehua (Metrosideros macropus) located in the wild?

Habitat:

Found up to 945 m elevation in the Ko'olau Mountains on the island of O'ahu.

Distribution:

Endemic to O'ahu.

States & Provinces:

`Ohi`a Lehua can be found in Hawaii

Which CPC Partners conserve `Ohi`a Lehua (Metrosideros macropus)?

Harold L. Lyon Arboretum

Not Sponsored

Assigned 10/25/19

CPC's Plant Sponsorship Program provides long term stewardship of rare plants in our National Collection. We are so grateful for all our donors who have made the Plant Sponsorship Program so successful. We are in the process of acknowledging all our wonderful plant sponsorship donors on our website. This is a work in progress and will be updated regularly.

Conservation Actions

Anna Sugiyama, Tim Kroessig

10/29/2019

Collected by Tim Kroessig at Lyon Arboretum at University of Hawaiʻi at Mānoa and Emily Grave at Laukahi Plant Conservation Network in Waʻahila Ridge, Honolulu Watershed Forest Reserve, Koolaun Mountaines on the island of Oʻahu, Hawaiʻi.

Metrosideros macropus occurs at mid elevation and higher. Therefore, the habitat has been relatively intact and population is stable with no imminent threat. However, invasive weeds, ungulates, pollinator bird losses may still threaten the species. Rapid Ohia Death (ROD) is currently unknown for Metrosideros macropus.

Due to the fact that Metrosideros macropus occurs in a narrow range of habitat, and only on ridges, accessibility is a challenge for collecting its seeds. In addition, fruits may take months to mature but if not collected immediately after, all the seeds may be lost. Progress of fruit maturity is hard to predict, and requires the collectors to visit repeatedly to be able to collect at the right time.

Seeds were free of predation but maturity ranged from slightly immature green to mature black. Therefore, they were post-harvest ripened. Seeds are small and often have low seed fill rate. For this accession, initial germination was 46% on agar substrate. Seeds of this species is storable for 15+ years and seeds stored at -18ºC are scheduled to be tested for long-term viability tests in 10 years.