Overview
The Maui Cyanea (Cyanea asplenifolia), known in Hawaiian botanical tradition as haha, is an extraordinary, critically endangered lobeliad shrub endemic exclusively to the island of Maui. Part of the renowned Hawaiian lobelioid adaptive radiation—the largest plant radiation in the archipelago—this remarkable plant is noted for its fern-like, deeply pinnate foliage, which strongly resembles the fronds of spleenwort ferns (Asplenium). Facing severe decline over the past century, it stands today as one of the most rigorously safeguarded botanical treasures in the Pacific.
Biology and Physical Characteristics
Cyanea asplenifolia grows as a palm-like or slender woody shrub reaching up to two meters in height, with a largely unbranched trunk bearing a crown of spreading leaves. Unlike the simple, undivided leaves of many related Cyanea species, its foliage is deeply incised with numerous narrow lobes, an adaptation believed to deter extinct flightless browsing waterfowl (moa-nalo). In late summer and autumn, the plant produces clusters of curved, tubular blossoms measuring approximately two inches in length. The corollas are whitish to pale lilac, accented with deep purple longitudinal striping designed to accommodate curved bird bills.
Behavior and Ecology
This specialized montane plant relies on an intimate evolutionary mutualism with Hawaii’s native honeycreepers (Drepanidinae). The curved architecture of the Cyanea flower matches the decurved bills of honeycreepers such as the Iiwi (Drepanis coccinea), which sip nectar while collecting pollen on their forehead feathers. After successful cross-pollination, the plant produces fleshy, orange-yellow berries that were historically dispersed by frugivorous forest birds. It grows primarily along sheer, mist-drenched ravine walls where soil moisture remains high and competition from dense understory shrubs is minimized.
Conservation and Human Impact
Cyanea asplenifolia is listed as Critically Endangered due to catastrophic habitat degradation caused by introduced feral pigs, goats, and axis deer, which uproot delicate gulch soils and devour saplings. Invasive mollusks, including introduced African snails and predatory slugs, feed voraciously on seedlings and floral buds. Furthermore, the extinction of several native avian pollinators has drastically reduced natural seed set. Conservationists from the Maui Cultural Lands and the Plant Extinction Prevention Program (PEPP) have installed ungulate-proof fences around relict populations and propagated clones in specialized botanical nurseries for wild outplanting.
Interesting Factoid
The deeply divided, fern-like leaves of Cyanea asplenifolia are thought to be an evolutionary defense developed millions of years ago to visually camouflage the plant from massive, flightless ‘moa-nalo’ grazing ducks that once roamed ancient Maui!
Last updated: October 2026