Sporobolus indicus (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Sporobolus indicus (L.) R. Br.

Family: Gramineae

Synonyms

Agrostis indica L., Sporobolus berteroanus Hitchc. & Chase, S. elongatus R.Br.

Vernacular names

• Smutgrass, West Indian dropseed (En)
• Indonesia: rumput rantai alat (Minangkabau), jukut nyenyerean (Sundanese), suket sadan (Javanese)
• Philippines: bakit (Panay Bisaya), lusai (Subanon), sangsangitan (Bontoc)
• Vietnam: cỏ lông công, xạ tử ấn.

Distribution

Widely distributed in the tropics. In South-East Asia it has been recorded throughout.

Uses

In West Java the culms are used to make brooms ("sapu nyere"). In the Philippines the fairly fine straw of the flower stalks as well as the rough culms are plaited into hats and fans. The culms have also been used for plaiting in Brazil and Madagascar. The grain is eaten in Bengal in times of food scarcity. S. indicus is widely used as a forage but it appears only valuable when young, becoming tough and fibrous once old. Its growth habit makes it a feared weed, although it is a suitable crop for erosion control.

Observations

A long-living annual grass, usually densely tufted, 0.5-1 m tall. Culm erect, slender, more or less compressed, glabrous, smooth. Leaves for the greater part crowded at base of culm; sheaths shortly ciliolate along margin, otherwise glabrous; ligule up to 0.5 mm long; blade linear, acute, margins smooth to scaberulous, 6-15 cm × 2-7 mm. Inflorescence a panicle; contracted, 7-60 cm long, dense; branches erect and often adpressed, lower ones 3-8 cm long; spikelets 1.3-2.6 mm long; lower glume up to 1 mm long; upper glume up to 1.7 mm long, oval-oblong, with attenuate or rounded, entire or slightly dentate apex, enervate or 1-nerved; palea as long as lemma or slightly shorter; stamens 2 or 3; anthers up to 1.1 mm long; stigma rather large, white. Fruit a utricle. Seed solitary, ovoid. Seedling with epigeal germination. Seed ellipsoid to oblong, about 1 mm in diameter, brown. S. indicus grows in dry sites, along roads and footpaths, in waste places, pastures and much trodden grass fields, preferring hard and stony soils. In Java it occurs in cool, rainy areas at 100-300 m altitude, and it flowers from January to December. Propagation is by seed and regrowth from rhizomes. Helminthosporium ravenelii may cause "sooty spike disease" on S. indicus. Several Bipolaris spp. cause the fungal disease "smut". S. indicus is a polymorphous species with 5 varieties being distinguished in the Malesian region. In California (United States) it is reported to cause contact dermatitis in some people.

Selected sources

5, 6, 19, 20, 71, 111, 133, 187.

Authors

M. Brink, P.C.M. Jansen & C.H. Bosch