Dichanthium annulatum
(Kleberg's bluestem)

Preferred Common Name

• Kleberg's bluestem

Other Scientific Names

• Andropogon annulatus Forssk.
• Andropogon garipensis Steud.
• Andropogon ischaemum Roxb. ex Wight
• Andropogon obtusus Nees ex Hook. & Arn.
• Andropogon scandens Roxb.
• Bothriochloa tuberculata W.Z. Fang
• Gymnandropogon annulatum (Forssk.) Duthie
• Lepeocercis annulata (Forssk.) Nees
• Sorghum annulatum (Forssk.) Kuntze

International Common Names

• English: angleton grass; bluestem; diaz bluestem; Hindi grass; Kleberg bluestem; marvel grass; ringed dichanthium; sheda grass; two-flowered goldenbeard; vunda blue grass
• Spanish: climacuna; pajón; pitilla; yerba de las travesías; yerba de vía
• Chinese: shuang hua cao

Local Common Names

• Cuba: pitilla americana
• India: delhi grass; jargu grass; karad
• Philippines: lindi
• Thailand: ya hindi; ya waen
• Vietnam: song tha'o to

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

The genus Dichanthium of the family Poaceae comprises 20 species native to the Old World, but hybrids between different species have been reported (Saxena and Chandra, 2006). The name Dichanthium comes from the Greek “dicha” = in two, as in two separate things, and “anthos” = flower, as a reference to the presence of homogamous and heterogamous spikelets (Barkworth et al., 2003). The species D. annulatum is highly apomictic and it can form hybrids with other species such as D. fecundum (Saxena and Chandra, 2006). Thus, a considerable morphological variation has been reported for this species (Agarwal et al., 1999).

D. annulatum is a perennial grass with culms 25-100 cm tall, ascending, nodes pubescent. Sheaths lax, terete, 3-4 cm long, glabrous except finely pubescent on margins near throat; ligule a shallow membrane, approximately 1.5 mm long; blades linear-acuminate, 3-30 cm long, 2-7 mm wide, margins sparsely pubescent, apex attenuate, base subcordate. Inflorescences composed of (1) 2-15 subdigitate, short-pedunculate racemes, each raceme 3-7 cm long, peduncles glabrous; spikelet pairs subimbricate along a slender filiform axis, with 0-6 smaller homogamous spikelet pairs at base, the joints and pedicels flattened, margins setose; sessile spikelet narrowly oblong, 2-6 mm long, first glume cartilaginous, slightly concave, villous below the middle, pubescent with long bulbous-based hairs above the middle, obscurely nerved, margins inflexed, apex obtuse to subacute, second glume narrowly boat-shaped, 2-6 mm long, 3-nerved, scabrid on back of the midnerve toward apex, obscurely scaberulous over the back toward apex, hyaline, first lemma delicately hyaline, oblong-rounded, setose near tip, approximately 2 mm long, palea absent, second lemma linear, approximately 1.6 mm long, hyaline, with the central nerve excurrent as a geniculate, twisted awn 8-25 mm long; pedicellate spikelet with first glume narrowly ovate-truncate, approximately 3 mm long, 11-nerved, pectinate-setose along the back of the inflexed margins, midnerve setose on the back toward apex. Caryopsis oblong to obovate, dorsally compressed, approximately 2 mm long (Wagner et al., 1999).

The date of the initial introduction of D. annulatum into new habitats is uncertain, but most likely it occurred during the late nineteenth or early twentieth century. For the West Indies, this species was first reported in 1915 in Cuba and in 1922 in Puerto Rico (US National Herbarium Collection). Between 1944 and 1954, the species D. annulatum and several cultivars were intentionally released in Texas, USA (Cook et al., 2005).

Soil drainage

• free

Soil reaction

• acid
• neutral

Soil texture

• heavy
• light
• medium

Special soil tolerances

• infertile
• saline

D. annulatum spreads mainly by seeds, but also by stolons. It produces large numbers of seeds which are mainly wind-dispersed. Seeds can also be dispersed secondarily by animals such as birds and by cattle, agricultural machinery and as a contaminant in grass seeds, agricultural products, and soil (Cook et al., 2005; FAO, 2014; Prota4U, 2013).

D. annulatum behaves as a grass weed and competes aggressively once established, often suppressing other species and forming dense stands. It has the potential to alter ecosystem functions by altering fire regimes, hydrology cycles, nutrient cycles, and community composition because it is drought-resistant and tolerates seasonal burning and saline conditions (Cook et al., 2005; Vibrans, 2011; FAO, 2014; PIER, 2014). In Australia, this species is highly invasive in arid wetlands where it is competing aggressively with important native grasses such as the species Eriachne benthamii (Queensland Department of Primary Industries and Fisheries, 2011). In Texas (USA), this species has escaped from cultivation and is outcompeting native grasses in bluestem coastal grassland communities (Barkworth et al., 2003; Queensland Department of Primary Industries and Fisheries, 2011).

• 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
• Has high reproductive potential
• Reproduces asexually

• Altered trophic level
• Ecosystem change/ habitat alteration
• Modification of fire regime
• Modification of hydrology
• Modification of nutrient regime
• Modification of successional patterns
• Monoculture formation
• Reduced native biodiversity
• Soil accretion
• Threat to/ loss of native species

• Competition - monopolizing resources
• Competition - smothering
• Competition - strangling
• Pest and disease transmission
• Herbivory/grazing/browsing
• Hybridization
• 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. annulatum is one of the most commercialized fodder grasses, especially in India and SE Asia because it is adapted to intense grazing and tolerates drought and fire (Duke, 1983). It is often planted as pasture for grazing and as a hay and silage grass. D. annulatum is also used for controlling soil erosion on sloping fields and to improve degraded grasslands (Cook et al., 2005; Prota4U, 2013).