Native Plants of Hawai‘i - Asplenium musifolium

Asplenium musifolium

(with notes on Asplenium nidus)

Asplenium musifolium has recently been classified as indigenous in the Hawaiian Islands, whereas Asplenium nidus is naturalized [Thomas et al. 2025]. The information on this Page will refer to Asplenium musifolium, unless otherwise noted.

Aspleniacaeae or Spleenwort family

Synonyms for Asplenium nidus: Neottopteris nidus, Tarachia polyphylla

Synonyms for Asplenium musifolium: Asplenium nidiforme, Asplenium nidus var. musifolium, Neottopteris musifolia, Neottopteris nidus var. musifolia, Thamnopteris musifolia,Thamnopteris nidus var. musifolia

ʻĒkaha

ʻĀkaha, ʻĒkaha kuahiwi

Natural Range & Environment

Asplenium musifolium is indigenous to Kauaʻi, Oʻahu, Lānaʻi (extinct), Molokaʻi, Maui, and Hawaiʻi Island in the Hawaiian Islands. It is also indigenous to Indonesia, Malaysia, the Philippines, New Guinea, and the Solomon Islands [Thomas et al. 2025].

Asplenium nidus is a relatively common naturalized fern on Kauaʻi, Oʻahu, Maui, and Hawaiʻi Island, 40-762 m (ca. 130-2,500 ft). A. nidus is native to SE Asia, Indo-Pacific, Pacific islands, Madagascar, and East Africa. Both Asplenium musifolium and A. nidus are found as epiphytes, lithophytes, or terrestrials where detritus collects and are often microcosms for animal species in the canopy or elevated on boulders [Thomas et al. 2025].

Nice examples of cultivated ʻēkaha (Asplenium musifolium) on an Oʻahu college campus.

ʻĒkaha often grow as an epiphyte in leaf debris with other natives such as here with moa nahele (Psilotum complanatum) in the crotch of a huge ʻahakea (Bobea elatior), an endemic tree in a mesic forest in the Koʻolau Mountains, Oʻahu. Habit of ʻēkaha in a natural setting (Second photo courtesy of [Thomas et al. 2025]).

Description

ʻĒkaha (Asplenium musifolium) is one of the most recognizable of all ferns in the Hawaiian Islands. It is distinguished by its impressive, broad fronds that can reach lengths of 3 to 5 feet (1 to 1.5 m), resembling the shape and texture of banana (Musa spp.) leaves. A notable feature of this fern is the abundance of long, parallel rows of sori—clusters of fern spores—adorning the undersides of its fronds, which impart a unique, rusty appearance. However, it can be confused with Asplenium nidus. One of the identifying characteristsics is the midrib of the frond. Please see the chart Key Differences Between two Asplenium sp.

Key Differences Between two Asplenium sp.

Asplenium musifolium

Indigenous to the Hawaiian Islands [Thomas et al. 2025].

Common Name:

Often called the "banana bird's nest fern" due to its large, broad fronds. In Hawai'i, it is known as ʻēkaha.

Native Range:

Native to regions including Southeast Asia and the Pacific, and it is properly referred to as ʻēkaha.

Frond Tip:

Features a broad, rounded tip.

Frond Width:

Broader fronds, growing up to 30 cm wide.

Midrib Cross-section:

The midrib very prominent on undersurface (especially in the basal half of the frond), weakly/somewhat prominent on upper surface to nearly flat, cross-section of midrib trapezoidal [Miles Thomas, pers. comm.]. In other words, the midrib is flat or gently rounded on the upper side with a prominent bulge on the underside of the midrib of the frond.

Scales (located on unfurling fronds. See Header photo.)

The cell wall color is dark red to black and larger, often twice the size when compared to A. nidus. The scales lack recurved, hooked-appendages.

Sori (Spore Clusters):

Shorter and more spread out. The sori of Asplenium musifolium extend the length of the frond and along the underside of the frond, typically stretching from the midrib outwards toward the margin. They are generally found on the outer, upper portion of the leaf, often in a herringbone pattern.

Asplenium nidus

Naturalized in the Hawaiian Islands [Thomas et al. 2025].

Common Name:

Most commonly known as the bird's-nest fern.

Native Range:

Widespread, with a native range from tropical areas of Africa, Asia, Australia, and Polynesia.

Frond Tip:

Has a tapering, pointed tip.

Frond Width:

Narrower fronds, growing up to 20 cm wide.

Midrib Cross-section:

Midrib mostly prominent on upper surface of frond, less prominent and rounded on the underside, often flat in the upper half of frond, cross-section rounded [Miles Thomas, pers. comm.]. In other words, a prominent and often square-like bulge on the upper side, and flat on the underside. It has a prominent top (adaxial) bulge on the top (upperside) of the midrib, which is part of the frond that faces the inside of the plant.

Scales (located on unfurling fronds.)

The cell wall color is dark red and is smaller when compared to A. musifolium. The scales have recurved hooked-appendages.

Sori (Spore Clusters):

Longer, extending up to half the width of the frond. The sori of Asplenium nidus do not extend the length of the frond; rather, they are located on the underside of the frond, typically appearing as rows of brown lines that extend outward from the central midrib toward the margin. They often appear in a herringbone pattern on either side of the dark midrib. The sori usually extend from the midrib about halfway to two-thirds (or sometimes three-quarters) of the way to the margin.

A cross-section of a frond of Asplenium musifolium in first of the above photos. Notice the bulge on the underside (bottom), and in the second photo showing the midrib of A. musifolium which is very flat, almost lacking in A. nidus in the next two photos. Also, an introduced species, Asplenium australasicum, is found in cultivation (at least on Oʻahu) and that one has a distinctly triangular cross section forming a somewhat sharp ridge on the bottom of the midrib [Miles Thomas, pers. comm.].

The first photo compares a scale of A. nidus (upper) with smaller cell walls, and hooked-appendages with a scale of A. musifolium (lower) lacking appendages and larger cells. All photos are courtesy of [Thomas et al. 2025]. The second photo is in a garden setting and displays A. nidus on the left and A. musifolium on the right.

It is good to keep in mind that local garden shops in Hawaiʻi may offer a variety of "Bird's-nest ferns" with numerous cultivars. However, if you are seeking to grow our native ʻēkaha (Asplenium musifolium), look for reputable growers such as those found at Where can you buy these plants?

Growth Requirements

General

These vibrant yet relatively slow-growing ferns make excellent accent plants for shaded to partially sunny areas beneath trees. They thrive in pots and hanging baskets, particularly in shaded locations such as on a north- or east-facing lanaʻi. Additionally, these ferns can be cultivated as indoor container plants and are well-suited for bathrooms, where humidity levels are typically higher.

While ʻēkaha can tolerate some sunlight, excessive exposure may scorch their leaves, resulting in an unsightly appearance. Fortunately, they often recover, albeit slowly, especially if new growth (emerging fronds) remains unaffected and the plants are relocated to a shadier environment.

These ferns can be utilized in various ways: planted directly in the ground (terrestrial), nestled among rocks or in crevices (lithophyte), or positioned on tree branches or within branch crotches as epiphytes. Smaller ferns can be secured to branches using twine or nylon stockings and should be kept moist until they establish roots. For an aesthetically pleasing display, consider placing them among large boulders, allowing ample space for their fronds to flourish. Larger ʻēkaha require additional support, as they may topple in windy conditions if not properly anchored. See the following illustrations and explanations to ensure that your fern is anchored and stable in a garden.
For potted ʻēkaha, apply a slow-release 13-13-13 fertilizer every six months. If larger potted ferns exhibit poor coloration or fail to produce crosiers (fiddleheads or emerging fronds), consider using a complete fertilizer at half the recommended strength. Kay Lynch (Lāʻau Hawaiʻi/Hawaiʻi Fern Project) suggests that it is important not to till solid fertilizers into the soil, as ferns possess a shallow root system that can be easily disturbed.

Pests and Diseases

Scale and whiteflies can be problematic. Refer to the Pests & Diseases page for treatments.

Since ʻēkaha can be top-heavy until established, a tried and proven method to give it an epiphytic look in a garden is to counter-balance the fern by providing weight at the bottom. This example shows a 7½" x 7½" block with a one-inch pipe and filled with quick-drying concrete. The concrete block can be placed partly or fully buried in the ground for extra stability. This setup will provide the required support for a dead hollow hapuʻu stump, which can be filled first with cinder, then a mixture of soil or potting mix and debris such as leaf litter. To provide even greater stability and weight, a pipe can first be driven into the ground, and then the block and cement added. Leave room for the ʻēkaha to be planted at the top. With generous amounts of water and partial sun, it will soon become another natural feature in your garden. This is only one variation of many, and you can modify it for your needs.

Uses

Ancient Hawaiian

The dark midribs of ʻēkaha fronds were intricately woven into lau hala mats and various other lau hala objects, providing a striking contrast in both pattern and color [Krauss 1993, Neal 1965].
D.M. Kaʻaiakamanu notes that a liquid derived from the leaf shoots of ʻēkaha, when combined with other plants, was traditionally used to treat children and infants suffering from ʻea (thrush) and pāʻaoʻao, a condition that causes physical weakness [Ka‘aiakamanu & Akina 1922]. Further, Kaʻaiakamanu says that the shoots were pounded together with other botanicals, and the resulting liquid was administered to children with mouth sores or general weakness. Additionally, an ointment made from the leaves, mixed with other ingredients, was applied to ulcers and body sores (known as pūhō kolokolo kokoʻole) [Ka‘aiakamanu & Akina 1922].
ʻĒkaha was ceremonially planted to conceal residual stumps after trees were felled for canoe (waʻa) construction, serving both a practical and symbolic purpose before the wood was shaped with an adze [Krauss 1993].

Modern

Special Features and Information

General

ʻĒkaha (Asplenium musifolium) belongs to one of the largest fern families, Apleniaceae or the Spleenwort family. There are 26 species of Asplenium ferns native to the Hawaiian Islands, 16 of which are endemic [Flora of the Hawaiian Islands]. Asplenium musifolium is indigenous to the Hawaiian Islands, but might be an endemic taxon pending further studies [Miles Thomas, pers. comm.].

On Oʻahu (southern Koʻolau Mts.) and Maui in dry to mesic forests, very young ʻēkaha, known as ʻēkahakaha, are frequently seen with an indigenous fern, ʻoheʻohe (Haplopteris elongata). The long, narrow fronds and rhizomes of ʻoheʻohe appear to look like aerial roots coming from the accompanying ʻēkaha. It is not clear if ʻoheʻohe is growing as an epiphyte on ʻēkaha or the reverse. There may be a mutual advantage [Palmer 2003].

Hawaiian Name

This fern is sometimes called ʻĒkaha kuahiwi, meaning "mountain ʻēkaha," to distinguish it from native mosses or from ʻĒkaha kuahiwi kū moana (black coral) [Hawaiian Dictionaries]. ʻĒkahakaha is a juvenile form of ʻēkaha [Palmer 2003]. ʻĀkaha is the same as ʻĒkaha [Hawaiian Dictionaries]. The names ʻĀkaha, Ēkaha, ʻĒkahakaha and ʻĒkaha kuahiwi also refer to Asplenium musifolium [Bishop Museum Plants of Hawai‘i].

Etymology

The generic epithet Asplenium is from the Latin word, asplenum, meaning spleenwort. Ancient Greeks believed this fern could cure diseases of the spleen [Palmer 2003].

The specific epithet musifolium, meaning leaves resembling Musa (Banana) [Gledhill 2008]. The former specific epithet nidus, nest or nest-like [Gledhill 2008].

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