Dichanthium caricosum
(nadi blue grass)

Preferred Scientific Name

• Dichanthium caricosum (L.) A.Camus

Preferred Common Name

• nadi blue grass

Other Scientific Names

• Andropogon annulatus var. subrepens Hack.
• Andropogon caricosus L.
• Andropogon depressus Steud.
• Andropogon filiformis Pers.
• Andropogon tenellus Roxb.
• Apocopis pallida Hook.f.
• Dichanthium caricosum var. theinlwinii (Bor) de Wet and Harlan
• Dichanthium pallidum (Hook.f.) Stapf ex C.E.C.Fisch.
• Dichanthium theinlwinii Bor
• Heteropogon concinnus Thwaites
• Heteropogon tenellus (Roxb.) Schult.
• Lepeocercis serrata Trin.
• Sorghum caricosum (L.) Kuntze

International Common Names

• English: angleton grass; Antigua haygrass; roadside bluestem
• Spanish: jiribilla
• Chinese: dan sui cao

Local Common Names

• Australia: roadside bluestem
• Cuba: jiribilla
• Fiji: nawai grass

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

The subfamily Panicoideae of the family Poaceae comprises around 212 genera and 3316 species most abundant in tropical and subtropical regions, particularly mesic portions of such regions, but several species grow in temperate regions of the world (Stevens, 2012). Dichanthium is a genus of 21 species (The Plant List, 2013) that grow in habitats ranging from subdeserts to marshlands in tropical Asia and Australia. The genus name derives from the Greek dicha, in two, as in two separate things, and anthos, flower, a reference to the presence of homogamous and heterogamous spikelets. Species within this genus are frequently found in disturbed areas, and some species are cultivated to provide good forage (Barkworth et al., 2003).

D. caricosum is a perennial, stoloniferous grass. Culms tufted at nodes of stolons, geniculately ascending, 30–60 cm tall, nodes glabrous or pubescent. Leaf sheaths compressed, keeled, shorter than internodes; leaf blades flat, 15–20 cm × 2.5–5 mm, glabrous or with a few hairs at base, margins smooth or scabrid, apex acuminate; ligule less than 1 mm, margin ciliate. Inflorescence terminal; peduncle glabrous; racemes (1–)2–4, 2.5–5 cm, with 1–3 pairs of homogamous spikelets. Sessile spikelet 3–3.5 mm; lower glume obovate-elliptic or obovate-oblong, papery, 8–12-veined, glabrous or often sparsely hirsute on lower back, slightly glossy, margins shortly ciliate, keels winged, apex rounded; upper glume ciliate above middle, apex obtuse; awn 1.5–2.5 cm, weakly geniculate. Caryopsis obovate-oblong. Pedicelled spikelet many-veined, resembling sessile (Flora of China Editorial Committee, 2015).

The date of the initial introduction of D.caricosum into new habitats is uncertain, but most likely it occurred during the late nineteenth or early twentieth century. In Cuba this species appears in collections made in 1910 in Havana and Pinar del Rio (US National Herbarium Collection). It has been recently introduced and is becoming popular in the Chaco region of northern Argentina (Cook et al., 2005).

Soil drainage

• free
• seasonally waterlogged

Soil reaction

• acid
• alkaline
• neutral

Soil texture

• light
• medium

Special soil tolerances

• shallow

D. caricosum spreads by seeds and vegetatively by stolons. It can also be dispersed as a seed contaminant (USDA-ARS, 2015). It is intentionally spread by stolons to establish permanent pastures (Cook et al., 2005).

D. caricosum is regarded as an environmental and agricultural weed (Randall, 2012). It is also listed as an invasive grass principally in dry habitats in Cuba and on islands in the Pacific Ocean (Smith, 1979; Oviedo Prieto et al., 2012; PIER, 2015). It has escaped from cultivation and it becomes a weed in disturbed sites, waste areas, and along roadsides. It has the capability to out-compete native species. In Cuba, it is one of the most aggressive invasive plants, very difficult to eradicate and widespread across the island (Catasús, 1997).

• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Highly adaptable to different environments
• Is a habitat generalist
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Highly mobile locally
• Benefits from human association (i.e. it is a human commensal)
• Long lived
• Fast growing
• Gregarious
• Reproduces asexually

• Ecosystem change/ habitat alteration
• Modification of fire regime
• Modification of hydrology
• Modification of successional patterns
• Monoculture formation
• Negatively impacts agriculture
• Reduced native biodiversity
• Threat to/ loss of native species

• Competition - monopolizing resources
• Competition - smothering
• Herbivory/grazing/browsing
• Rapid growth
• Rooting

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

D. caricosum is often planted for permanent pastures and erosion control. It is tolerant of heavy grazing and fire and it is cultivated to be used as animal forage and fodder. It is palatable and readily eaten by cattle, sheep, goats and horses (Cook et al., 2005; FAO, 2015; USDA-ARS, 2015).