Native Plants of Hawai‘i

Bobea elatior

Rubiaceae or Coffee family

Synonyms: Bobea gaudichaudii, Bobea platypes, Burneya gaudichaudii, Timonius gaudichaudii

ʻAhakea lau nui

ʻAhakea

Natural Range & Environment

ʻAhakea lau nui (Bobea elatior) is the most widespread species of the genus. It occurs in mesic valleys and mesic to wet forests from 250-1,100 m (c. 492-3,608 ft) Kauaʻi (Nāpali Coast south-eastward to Hāʻupu Ridge), Oʻahu (Koʻolau Mountains), Molokai, Lānaʻi, Maui, and Hawaiʻi Island (Kohala Mountains) [Wagner et al. 1990].

ʻAhakea lau nui is easy to grow as a cultivated tree. The size of the leaves of this cultivated plant shows how this species got its Hawaiian name, lau, meaning leaf, and nui, meaning big. The opposite arrangement of the leaves is a characteristic of this species. Flower, fruit (here unripe) and habit of a large wild tree in the Koʻolau Mts., Oʻahu, with epiphytic plants (e.g., ʻēkaha) growing in the crotch of branches.

Description

ʻAhakea lau nui can be a shrub or a tree, reaching up to 15 meters (c. 45 ft) tall. The leaves are simple and opposite, with blades that are elliptic to obovate. The surface of the leaves is usually smooth with domatia (small indentations), and the margins are entire. The inconspicuous, greenish-white or greenish-yellow flowers appear in cymes (flower clusters) of 1 to 7. The purplish drupes can have 2 to 6 nutlets, each containing one seed. The bark is dark brown and rough with vertical fissures on mature trees.

Growth Requirements

General

ʻAhakea lau nui, though rarely seen in cultivation, is easy to grow and care for in the landscape and is not too particular about soil conditions as long as there is sufficient sunlight for it to thrive. However, I (Eickhoff) have found that the afternoon sun, especially in the summer, can scorch the large leaves of young saplings and should be protected. As a container plant, use a generous amount of lava cinders within the potting soil mix and in the bottom of the container will ensure good drainage as well as add some weight to the tub to avoid tipping over. Eventually, though, ʻahakea lau nui may outgrow even the largest containers and will likely need to go into the ground in a location to accommodate the potential size of a mature tree, which can grow quite large.

Potted plants respond well to fertilizers, but avoid high nitrogen fertilizers, which may cause luxuriant growth but fewer flowers and fruit. I have good results with kelp emulsion as a fertilizer at a dilution of one-half to one-third of the recommended strength applications in the container and for foliar feeding monthly.

With its ease of cultivation, is too bad that this species is not seen more in private gardens and public places. Likely, it is a matter of availability of seeds and other growing material that limits our seeing it more.

Pests and Diseases

ʻAhakea lau nui is prone to ants, scale, mealybugs, thrips, red spider mites and aphids. Black twig borers may cause minor damage at first, but must be treated immediately, or they can destroy the entire tree. Refer to the Pests & Diseases page for treatments.

Uses

Ancient Hawaiian

ʻAhakea wood was highly valued in traditional Hawaiian canoe (waʻa) construction. Its hard, yellowish, or reddish wood was the preferred choice for crafting gunwale strakes (moʻo), the forward end piece (lāʻau ihu), and the aft piece (lāʻau hope) [Krauss 1993, Abbott 1992]. The moʻo were left unpainted, providing a pleasing contrast to the black-painted body of the waʻa [Krauss 197-]. Canoe paddles were also crafted from ʻahakea wood [Medeiros et al. 1998].

In house construction, ʻahakea was favored for framing hale (house) doorways and door frames (lapauila) due to its reddish or yellowish hue, which was considered a chiefly color.

For household furnishings, ʻahakea was used to make poi boards (papa kuʻi poi) because of its close-grained wood [Mitchell 1992]. Bowls were also crafted from this durable wood [8].

Medicinally, Ka‘aiakamanu 1998 asserts that ʻahakea, when mixed with kukui nuts, was used to treat abscesses, burst sores (ʻili pūhō), scars, possibly tuberculosis (ʻalaʻala), and itch or ulcers (meʻeau), and the bark and leaves were boiled for bathing purposes. Native Hawaiian Medicine notes another treatment for abscesses involved using ʻahakea bark ground with the root bark of puakala ku kula (Argemone glauca), bark of ʻōhia ‘ai (Syzygium malaccense), and Coffee senna or ‘auko‘i (Senna occidentalis), then placed in a mai‘a (banana) and used as a poultice [Chun 1994].

Hawaiian Dictionaries notes how ʻahakea was used in a conversation, "I ke aha hoʻi? I ka ʻahakea. Why then? The ʻahakea [a saucy, retort containing a pun on the word aha, what]."

Modern:

Special Features and Information

General

Bobea belongs to the Coffee family (Rubiaceae) and is represented by four species (B. brevipes, B. elatior, B. sandwicensis, B. timonioides) in the endemic Hawaiian genus Bobea, with all four being found on Oʻahu [Wagner et al. 1990].

Hawaiian Name

Of the four species of Bobea, only two have known Hawaiian names. The featured species Bobea elatior, is known by ʻAhakea lau nui, meaning ʻAhakea with large (nui) leaves (lau), in contrast to B. brevipes, with the name ʻAhakea lau liʻi, which means ʻAhakea with small (liʻi) leaves (lau). Additionally, B. brevipes also has the name ʻakupa, a name used for a native ʻoʻopu (gobby).

Etymology

The generic name Bobea was named by Charles Gaudichaud-Beaupré in 1830 for Jean-Baptiste Bobe-Moreau, physician and pharmacist in the French Marine [Wagner et al. 1990]. The specific epithet elatior is Latin for taller [Gledhill 2008].

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