Setaria palmifolia
(palm grass)

Preferred Common Name

• palm grass

Other Scientific Names

• Panicum palmaefolium J. Koenig (1788)
• Panicum palmifolia J. Koenig (1788)
• Setaria lenis (Steud.) Miq. (1857)

Local Common Names

• English: bristlegrass; broadleaved bristlegrass; hailans pitpit; highland pitpit; knotroot; palmgrass; short pitpit
• Australia: pleated pigeon grass
• China: you gou wei cao; zhu tou cao; zhu ye cao; zong mao; zong ye cao; zong ye gou wei cao
• France: que de rat
• India: aruna; dhutesaro
• Indonesia: lintabung; rumput daun pisang
• Japan: sasa kibi
• Papua New Guinea: kura; pitpit
• Philippines: agusas
• Samoa: vao ‘ofe‘ofe
• Spain: pasto de palma
• Thailand: ya kap phai
• USA/Hawaii: mau‘u Kaleponi

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Monocotyledonae
•                     Order: Cyperales
•                         Family: Poaceae
•                             Genus: Setaria
•                                 Species: Setaria palmifolia

Many other synonyms are listed by The Plant List (2012) in addition to those included in the Identity section. It was originally given the name Panicum palmifolium (also recorded as P. palmaefolium or P. palmifolia) by Koenig in 1788. It was first included in the genus Setaria as Setaria lenis in 1857. It has been given many other names within Agrostis, Panicum, Chaetochloa, Chamearaphis and Setaria. None of these are in current use, though the alternative spelling as S. palmaefolia occasionally occurs. Shukla (1996) comments that ‘this variable species approaches S. plicata on one hand and S. poiretiana on the other’ and some authors have suggested that the former is merely a depauperate form of S. palmifolia (e.g. Noltie, 2000).

S. palmifolia is a densely tufted perennial grass with short, woody, knotty rhizomes, with foliage up to 1 m high. Individual leaves 20-60 cm long, 2-7 cm, wide, plicate (finely pleated with multiple ridges) glabrous or hispid, narrowed toward the base, apex acuminate. Leaf sheath hispid with irritant haitrs, ciliate near the ligule which is 2.5-3.5 mm long, also ciliate. Flowering culms may be decumbent at the base and rooting at the nodes, finally erect to 100-200 cm high, 5-8 mm diameter, nodes hairy. Panicle up to 60 cm long, 10 cm wide with branches each up to 20 cm, spreading, flexous. Spikelets 3-4 mm long, lanceolate, acute, some subtended by single bristles up to 15 mm long. Lower glume triangular, up to half as long as spikelet, upper glume 2/3 as long as spikelet, 5-7-nerved. Upper lemma somewhat rugose, shiny.  Caryopsis 2 mm long.

No precise information is available but records suggest introductions prior to 1923 in Australia, 1927 in Madagascar, 1939 in Belize, 1958 in New Zealand, 1964 in Liberia, 1971 in Venezuela, 1976 in Ethiopia, 1983 in Tenerife, 1994 in Uganda and 1996 in Niger and Zambia (GBIF, 2012).

Soil drainage

• free

Soil reaction

• acid
• neutral

Soil texture

• light
• medium

Natural Dispersal (Non-biotic)

No documentation is available but local dispersal is certain to occur by wind and by soil or water movement.

Vector Transmission (Biotic)

Shiels (2011) showed that seeds of S. palmifolia could be dispersed by rats in Hawaii, but less than 15% of the seeds survived the passage through the gut. Presumably domestic livestock could also cause dispersal on a local basis. PIER (2012) indicates dispersal by seed-eating birds.

Accidental Introduction

The seeds are very small and inconspicuous and could readily be introduced as contaminants of other pasture grass seed.

Intentional Introduction

Deliberate introduction continues to be highly probable as this species is widely advertised and made available as an ornamental plant. Several varieties are recognized including some with red foliage.

S. palmifolia is recorded as a weed of transplanted rice in Indonesia, upland rice in Thailand and Vietnam and also in unspecified rice systems in India and Nepal (IRRI, 1989). It can be abundant in tea plantations in Assam and has been recorded in wheat in Kashmir, but there are no data on economic losses or other costs incurred.

Growing wild in Assam, India, it gives fresh fodder yields of about 110.6 t/ha in 4 cuts. In trials with Jersey X Danish Red calves fed S. palmifolia ad lib., average dry matter intake was 2.1 kg/100 kg live-weight. The grass contained 8.8% digestible crude protein (DCP), 579% total digestible nutrients (TDN) and 48.5% starch equivalent. The calves showed positive balance for N, Ca and P (Bora et al., 1990). Protein was considered of good quality (Bradbury et al., 1985).

It is included in a mix of grasses fed to cattle in Sikkim (Das, 2005) and is regarded as an important component of natural pastures for goats in Meghalaya (Singh and Mudgal, 1999). Its nutritive value of was estimated in goats: the grass contained 47.6% TDN, 8.16% DCP and 28% starch equivalent with a nutritive ratio of 1:4.8; however, Gupta and Balaraman (1988) concluded that intake of grass in terms of TDN and minerals were inadequate to meet maintenance requirements of goats.

S. palmifolia is included among the valuable food plants for wildlife in the Mahananda wildlife sanctuary and other wildlife reserves of north Bengal, India (Ghosh, 1994).

S. palmifolia is among the plants posing a specific threat to endangered species Poa mannii and Phyllostegia warshaueri in Hawaii (US Fish and Wildlife Service, 1998; 2010).

PIER (2012) records it as invasive in Australia, New Zealand and on a number of Pacific Islands. Vigorous, monospecific stands of S. palmifolia occur in the Vailima Reserve and the Alaoa area in Samoa (Space and Flynn, 2002). The concern in these cases is mainly regarding threats to natural vegetation rather than to crops.

It is regarded as an environmental weed in Queensland and New South Wales, Australia, but has not been declared or considered noxious by any state government authorities.

• Invasive in its native range
• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Tolerant of shade
• Long lived
• Fast growing
• Has high reproductive potential
• Has propagules that can remain viable for more than one year

• Ecosystem change/ habitat alteration
• Monoculture formation
• Negatively impacts agriculture
• Negatively impacts forestry
• Threat to/ loss of endangered species
• Threat to/ loss of native species

• Competition - monopolizing resources
• Competition - shading
• Rapid growth

• Highly likely to be transported internationally deliberately
• Difficult to identify/detect as a commodity contaminant

The main economic use of S. palmifolia is as an ornamental plant. Seed is widely available on the internet and the plant is valued for its robust, striking palm-like foliage. 

It is not clear how often it is deliberately planted as a forage but where it occurs as a natural component of pasture, it regarded as of reasonable value though not as productive as many other species.

S. palmifolia has been used in the past as a human food source (Austin, 2006) and may still be in Papua New Guinea (FAO, 2012). It is also used for medicinal purposes, e.g. by the Mek tribes in Iranian Jaya, New Guinea (Plarre, 1995). In Perak a decoction is drunk for irregular menses and in the Philippines it is mixed with ashes of burned leaves to treat skin disorders (Plants for Use, 2012).

It is also used as shading material in plant nurseries.