Micronesian Names by Islands or Island Groups:  Dodoan (Yap) Description: Helminthostachys zeylanica is a relatively small fern with clusters of sporangia on stems of fertile, spike-like fronds 15-40 cm (6-16 in) tall. The leaves of this annual herb grow singly from a stout, creeping, underground rhizome. The rhizome can bear either single or multiple fronds. The leaves are lanceolate with the margins entire or irregularly serrate. The leaf blade spreads out almost horizontally, resembling an umbrella. It has three segments, each of which may be divided into two to five parts. The frond spike arises from the stalk at the base of the leaves with its own stipe. Below the spike is a sterile leafy segment (the trophophore). Both it and the sporophore arise from a common petiole. The upper part of the spike contains the spores.

Distribution: The geographical origin of Helminthostachys zeylanica is undetermined. However, it is known to be widespread at low elevations in South Asia, southern China, and throughout much of South-East Asia to tropical Australia and into the western Pacific, including Guam, Palau (Babeldaob), and Yap. It is found in open bushy places near sea level, in moist ground, especially along the banks of streams, often occurring in thickets around bamboo clumps. New fronds usually develop during the beginning of rainy periods.

General Uses: Helminthostachys zeylanica fern is reportedly grown as an ornamental in some tropical gardens in South and Southeast Asia, and its young fronds are gathered and consumed rather extensively, either raw in a salad or as a cooked vegetable, at least in some parts of the Philippines (e.g., Brown 1920:39-40). In addition, H. zeylanica has a number of therapeutic uses over its widespread range. For example, rhizomes of are harvested from the wild in some regions for medicinal use (e.g., see Burkill 19351136-1137). In China, the rhizomes, known as “Di wu gong,” have long been used in popular medicine, so much so that H. zeylanica is reportedly rare in China now due to over use and habitat alteration. Indeed, the rhizomes of H. zeylanica, have been a relatively common source of medicine in China, where it has been traditionally “harvested during the wet season in July–August.” In Java, the rhizome is said to be used to treat dysentery and for catarrh, and in Malaysia, the leaves are dried and smoked to treat bleeding nose, and the rhizome is reportedly used as a tonic and is consumed with betel nut for treatment of whooping cough; in India, the plant is eaten as a vegetable by mountainous tribal peoples and said to be used medicinally for “vitality” and as a “brain tonic,” while it is also used for liver ailments among a tribal group in Kerala (e.g., see Huang et al. 2009 and Perumal 2010). As a fiber source in areas of Java and the Philippines, petioles of old leaves are reportedly used in wickerwork and handicraft; e.g., see https://uses.plantnet-project.org/en/Helminthostachys_zeylanica_(PROSEA).

Uses by Island or Island Group in Micronesia: Raulerson listed only Guam as an island in the Marianas where this fern had been recorded; Fosberg et al. (1982:29) listed botanical collection records for Helminthostachys zeylanica from Palau (Babeldaob), and Yap.

Uses in Yap: According to Okabe (see Defillips et al. 1988:5), Helminthostachys zeylanica has been used medicinally on Yap for treating “lacquer poisoning,” which probably refers to a toxic reactionfrom contact with the sap of Changath, the native Semecarpus venenosa tree. Okabe reported that “coconut oil is heated and applied to the affected part by means of the ‘flower-stalk’ of this fern.” In addition, Okabe (see Defillips et al. 1988:22), indicated that parts of the H. zeylanica fern have been used to treat leprosy: “leaves [of the deadly nightshade species Solanum torvum Sw., known as Rawelnagafi in Yap] are crushed together with leaves of Helminthostachys zevlanica, mixed with coconut oil and applied to the affected part…[and] four or five ripe fruits of both [of these] species are eaten fresh every day.”