Dichanthium caricosum
(nadi blue grass)

Identity

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

Summary of Invasiveness

D. caricosum has been intentionally introduced as a perennial grazing pasture with excellent ground cover. Now, it can be found widely naturalized in tropical and subtropical regions (Cook et al., 2005; FAO, 2015). It has escaped from cultivation and has become a weed and invasive grass in Cuba, Guam, New Caledonia, and Fiji (MacKee, 1994; Oviedo Prieto et al. (2012); PIER, 2015). In Cuba, it is widespread across the islands. In Fiji, it covers large areas being very common especially in the dry zones, in pastures, canefields, waste places, and along roadsides (Smith, 1979). D. caricosum is a fast-growing gregarious grass that competes aggressively with other plants including other weeds (Cook et al., 2005).

Taxonomic Tree

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

Notes on Taxonomy and Nomenclature

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).

Description

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).

Plant Type

Distribution

D. caricosum is native to tropical Asia from India to China and Malesia (Clayton et al., 2015). It has been introduced across tropical areas and now it can be found widely naturalized elsewhere (see distribution table for details; PIER, 2015; PROTA, 2015; USDA-ARS, 2015).

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

History of Introduction and Spread

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).

Risk of Introduction

The risk of introduction of D.caricosum is moderate to high. It has been intentionally introduced in tropical and subtropical regions to be used as a fodder and forage grass (Cook et al., 2005; FAO, 2015). It has escaped from cultivation and rapidly colonizes new areas, mainly disturbed sites. Additionally, D.caricosum is fire and drought tolerant, which are features helping this species to colonize and invade new areas (Cook et al., 2005; FAO, 2015).

Habitat

D. caricosum grows in dry and moist habitats. It is common in dry zones, waste places, swampy places, open humid woodland, hill slopes, pastures, and along roadsides (Smith, 1979; Flora of China Editorial Committee, 2015). In India, it prefers to grow in dry, sandy habitats (FAO, 2015).

Habitat List

Hosts/Species Affected

D. caricosum is a common weed with negative impact in pastures and sugarcane fields (Smith, 1979).

Host Plants and Other Plants Affected

Biology and Ecology

Genetics

The chromosome number reported for D. caricosum is 2n = 40, 60 (Sinha et al., 1990).

Physiology and Phenology

In China, D. caricosum has been recorded flowering and fruiting from October to March (Flora of China Editorial Committee, 2015). In Fiji, it flowers in May and June at the beginning of the dry season after which the quality and quantity of growth decline rapidly (Partridge and Ranacou, 1974).

Environmental Requirements

D. caricosum can be found growing at elevations from 600-1000 m. It is well adapted to moist habitats (i.e., 1500-2500 mm rainfall) with a moderate dry season of 5-6 months. It prefers full sunlight but will grow under moderate shade. Commonly found on heavier (black) clays of moderate fertility. Such soils are generally slightly acid to alkaline.

D. caricosum is quite tolerant of waterlogging and is suited to the waterlogged black clays. It has been reported growing on sandy soils in southern India. This species has poor salt tolerance (Cook et al., 2005; FAO, 2015).

Climate

Air Temperature

Rainfall

Soil Tolerances

Soil drainage

• free
• seasonally waterlogged

Soil reaction

• acid
• alkaline
• neutral

Soil texture

• light
• medium

Special soil tolerances

• shallow

Natural enemies

Notes on Natural Enemies

D. caricosum is susceptible to root-knot nematodes on lighter soils. Plants infected by downy mildew fungus (Peronosclerospora sorghi) have been identified in Thailand (Cook et al., 2005).

Means of Movement and Dispersal

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).

Pathway Causes

Pathway Vectors

Impact Summary

Environmental Impact

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).

Risk and Impact Factors

• 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

Uses

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).

Uses List

Animal feed, fodder, forage

• Fodder/animal feed
• Forage

Prevention and Control

Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.

No information is available for the chemical or mechanical control of this species. However, other Dichanthium species are susceptible to glyphosate (Cook et al., 2005).

References

Acevedo-Rodríguez P, Strong MT, 2012. Catalogue of the Seed Plants of the West Indies. Smithsonian Contributions to Botany, 98:1192 pp. Washington DC, USA: Smithsonian Institution. http://botany.si.edu/Antilles/WestIndies/catalog.htm

AusGrass2, 2015. Grasses of Australia. Online Resources. http://ausgrass2.myspecies.info/

Barkworth ME, Capels KM, Long S, Piep MB, 2003. Flora of North America. Volume 25. Magnoliophyta: Commelinidae (in part): Poaceae, part 2. New York, USA: Oxford University Press. 783 pp..

Catasús LJ, 1997. Las gramíneas (Poaceae) de Cuba, I. Madrid, Spain: Cyanus S.L. .

Chong KY, Tan HTW, Corlett RT, 2009. A checklist of the total vascular plant flora of Singapore: native, naturalised and cultivated species. Singapore: Raffles Museum of Biodiversity Research, National University of Singapore, 273 pp. http://lkcnhm.nus.edu.sg/nus/pdf/PUBLICATION/LKCNH%20Museum%20Books/LKCNHM%20Books/flora_of_singapore_tc.pdf

Clayton WD, Govaerts R, Harman KT, Williamson H, Vorontsova M, 2015. World Checklist of Poaceae. Richmond, UK: Royal Botanic Gardens, Kew. http://apps.kew.org/wcsp/

Cook BG, Pengelly BC, Brown SD, Donnelly JL, Eagles DA, Franco MA, Hanson J, Mullen BF, Partridge IJ, Peters M, Schultze-Kraft R, 2005. Tropical Forages: an interactive selection tool. Brisbane, Australia: CSIRO, DPI&F, CIAT, ILRI. http://www.tropicalforages.info/

FAO, 2015. Grassland species profiles. Rome, Italy: Food and Agriculture Organization of the United Nations. http://www.fao.org/ag/agp/AGPC/doc/Gbase/Default.htm

Flora of China Editorial Committee, 2015. Flora of China. St. Louis, Missouri and Cambridge, Massachusetts, USA: Missouri Botanical Garden and Harvard University Herbaria. http://www.efloras.org/flora_page.aspx?flora_id=2

Fosberg FR, Sachet MH, Oliver RL, 1987. A geographical checklist of the Micronesian monocotyledonae., Micronesica, 20:1-126

Judziewicz EJ, 1990. Family 187. Poaceae (Gramineae). 8: 1–727. In: Görts-van Rijn ARA, Ed. Fl. Guianas, ser. A, Phanerog. Königstein, Germany: Koeltz Scientific Books.

MacKee HS, 1994. Catalogue of introduced and cultivated plants in New Caledonia. (Catalogue des plantes introduites et cultivées en Nouvelle-Calédonie). Paris, France: Muséum National d'Histoire Naturelle. 164 pp..

McCormack G, 2007. Cook Islands Biodiversity Database, Version 2007. Cook Islands Biodiversity Database. Rarotonga, Cook Islands: Cook Islands Natural Heritage Trust. http://cookislands.bishopmuseum.org/search.asp

Oviedo Prieto R, Herrera Oliver P, Caluff MG, et al. , 2012. National list of invasive and potentially invasive plants in the Republic of Cuba - 2011. (Lista nacional de especies de plantas invasoras y potencialmente invasoras en la República de Cuba - 2011). Bissea: Boletín sobre Conservación de Plantas del Jardín Botánico Nacional de Cuba, 6(Special Issue 1):22-96.

Partridge IJ, Ranacou E, 1974. The effects of supplemental Leucaena leucocephala browse on steers grazing Dichanthium caricosum in Fiji., Tropical Grasslands, 8:107-112

PIER, 2015. Pacific Islands Ecosystems at Risk. Honolulu, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

PROTA, 2015. PROTA4U web database. Wageningen, Netherlands: Plant Resources of Tropical Africa. http://www.prota4u.org/search.asp

Randall RP, 2012. A Global Compendium of Weeds. Perth, Australia: Department of Agriculture and Food Western Australia, 1124 pp. http://www.agric.wa.gov.au/objtwr/imported_assets/content/pw/weed/global-compendium-weeds.pdf

Raulerson L, 2006. Checklist of Plants of the Mariana Islands. , University of Guam Herbarium Contribution, 37:1-69

Sinha RRP, Bhardwaj AK, Singh RK, 1990. SOCGI plant chromosome number reports—IX., Journal of Cytology and Genetics, 25:140–143

Smith AC, 1979. Flora Vitiensis nova: a new flora of Fiji. Volume 1 . Lawai, Kauai, Hawaii, USA: National Tropical Botanic Gardens. 494 pp.

Soreng RJ, Davidse G, Peterson PM, Zuloaga FO, Judziewicz EJ, Filgueiras TS, Morrone O, 2003. Dichanthium. In: Catalogue of New World Grasses (Poaceae): III. Subfamilies Panicoideae, Aristidoideae, Arundinoideae, and Danthonioideae. , Contributions from the United States National Herbarium, 46:190-197

Stevens PF, 2012. Angiosperm Phylogeny Website. http://www.mobot.org/MOBOT/research/APweb/

The Plant List, 2013. The Plant List: a working list of all plant species. Version 1.1. London, UK: Royal Botanic Gardens, Kew. http://www.theplantlist.org

USDA-ARS, 2015. Germplasm Resources Information Network (GRIN). Online Database. National Germplasm Resources Laboratory, Beltsville, USA. http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl

Vivier M, Doreau M, 1979. Natural Dichanthium caricosum grassland in Guadeloupe., Agronomie Tropicale, 34:362–371

Distribution References

Acevedo-Rodríguez P, Strong M T, 2012. Catalogue of the Seed Plants of the West Indies. Washington, DC, USA: Smithsonian Institution. 1192 pp. http://botany.si.edu/Antilles/WestIndies/catalog.htm

AusGrass2, 2015. Grasses of Australia., http://ausgrass2.myspecies.info/

Chong KY, Tan HTW, Corlett RT, 2009. A checklist of the total vascular plant flora of Singapore: native, naturalised and cultivated species., Singapore, Raffles Museum of Biodiversity Research, National University of Singapore. 273 pp. http://lkcnhm.nus.edu.sg/nus/pdf/PUBLICATION/LKCNH%20Museum%20Books/LKCNHM%20Books/flora_of_singapore_tc.pdf

Clayton WD, Govaerts R, Harman KT, Williamson H, Vorontsova M, 2015. World Checklist of Poaceae., Richmond, UK: Royal Botanic Gardens, Kew. http://apps.kew.org/wcsp/

Cook BG, Pengelly BC, Brown SD, Donnelly JL, Eagles DA, Franco MA, Hanson J, Mullen BF, Partridge IJ, Peters M, Schultze-Kraft R, 2005. Tropical Forages: an interactive selection tool., Brisbane, Australia: CSIRO, DPI&F, CIAT, ILRI. http://www.tropicalforages.info/

Flora of China Editorial Committee, 2015. Flora of China., St. Louis, Missouri; Cambridge, Massachusetts, USA: Missouri Botanical Garden and Harvard University Herbaria. http://www.efloras.org/flora_page.aspx?flora_id=2

Fosberg FR, Sachet MH, Oliver RL, 1987. A geographical checklist of the Micronesian monocotyledonae. In: Micronesica, 20 1-126.

Judziewicz EJ, 1990. Family 187. Poaceae (Gramineae). In: Fl. Guianas, ser. A, Phanerog, 8 [ed. by Görts-van Rijn ARA]. Königstein, Germany: Koeltz Scientific Books. 1–727.

MacKee H S, 1994. Catalogue des plantes introduites et cultivées en Nouvelle-Calédonie. Paris, France: Muséum National d'Histoire Naturelle. unpaginated.

McCormack G, 2007. Cook Islands Biodiversity Database, Version 2007.2. In: Cook Islands Biodiversity Database, Version 2007.2, Rarotonga: Cook Islands Natural Heritage Trust. http://cookislands.bishopmuseum.org

Oviedo Prieto R, Herrera Oliver P, Caluff M G, et al, 2012. National list of invasive and potentially invasive plants in the Republic of Cuba - 2011. (Lista nacional de especies de plantas invasoras y potencialmente invasoras en la República de Cuba - 2011). Bissea: Boletín sobre Conservación de Plantas del Jardín Botánico Nacional de Cuba. 6 (Special Issue No. 1), 22-96.

PIER, 2015. Pacific Islands Ecosystems at Risk., Honolulu, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

PROTA, 2015. PROTA4U web database., Wageningen, Netherlands: Plant Resources of Tropical Africa. http://www.prota4u.org/search.asp

Raulerson L, 2006. Checklist of Plants of the Mariana Islands. In: University of Guam Herbarium Contribution, 37 1-69.

Smith AC, 1979. Flora Vitiensis nova: a new flora of Fiji., 1 Lawai, Kauai, Hawaii, USA: National Tropical Botanic Gardens. 494 pp.

Soreng RJ, Davidse G, Peterson PM, Zuloaga FO, Judziewicz EJ, Filgueiras TS, Morrone O, 2003. (Dichanthium). In: Catalogue of New World Grasses (Poaceae): III. Subfamilies Panicoideae, Aristidoideae, Arundinoideae, and Danthonioideae. , Contributions from the United States National Herbarium, 46 190-197.

USDA-ARS, 2015. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysimple.aspx

Vivier M, Doreau M, 1979. Natural Dichanthium caricosum grassland in Guadeloupe. In: Agronomie Tropicale, 34 362-371.

Links to Websites

Contributors

19/05/16 Original text by:

Julissa Rojas-Sandoval, Department of Botany-Smithsonian NMNH, Washington DC, USA

Distribution Maps