Leptochloa fusca
(sprangletop)

Preferred Common Name

• sprangletop

Other Scientific Names

• Atropis carinata Griseb.
• Brizopyrum uninervium (J.Presl) E.Fourn.
• Bromus polystachios Forssk.
• Centotheca malabarica (L.) Merr.
• Cynodon fascicularis (Lam.) Raspail
• Diachroa procumbens (Muhl.) Nutt.
• Digitaria malabarica (L.) Roem. & Schult.
• Diplachne acuminata Nash
• Diplachne amboensis Roiv.
• Diplachne capensis (Nees) Nees
• Diplachne carinata (Griseb.) Hack. ex Kurtz
• Diplachne fascicularis (Lam.) P.Beauv.
• Diplachne fusca (L.) P. Beauv. ex Roem. & Schult.
• Diplachne imbricata (Thurb.) Scribn.
• Diplachne indica (Retz.) Spreng.
• Diplachne livida Nees
• Diplachne malabarica (L.) Merr.
• Diplachne maritima E.P.Bicknell
• Diplachne muelleri Benth.
• Diplachne pallida Hack.
• Diplachne parviflora (R.Br.) Benth.
• Diplachne polystachya (Forssk.) Backer
• Diplachne procumbens Arechav.
• Diplachne reptatrix (L.) Druce
• Diplachne tarapacana Phil.
• Diplachne tracyi Vasey
• Diplachne uninervia (J.Presl) Parodi
• Diplachne verticillata Nees & Meyen
• Diplachne virens (Nees) Parodi
• Diplachne wahlbergii Roiv.
• Eragrostis procera (Roxb.) Steud.
• Eragrostis uninervia (J.Presl) Steud.
• Festuca brownii F.Muell.
• Festuca clandestina Muhl.
• Festuca digitata Brouss. ex Hornem.
• Festuca fascicularis Lam.
• Festuca fusca L.
• Festuca indica Retz.
• Festuca multiflora Walter
• Festuca polystachya Michx.
• Festuca reptatrix L.
• Festuca texana Steud.
• Festuca thouinii Steud.
• Hemigymnia malabarica (L.) Henrard
• Leptochloa acuminata (Nash) Mohlenbr.
• Leptochloa contracta (Retz.) Blatt. & McCann
• Leptochloa fascicularis (Lam.) A.Gray
• Leptochloa ginae Maire
• Leptochloa imbricata Thurb.
• Leptochloa malabarica (L.) Veldkamp
• Leptochloa muelleri (Benth.) Stace
• Leptochloa neuroglossa Peter
• Leptochloa polystachya (Michx.) Kunth
• Leptochloa tracyi (Vasey) Beal
• Leptochloa uninervia (J.Presl) Hitchc. & Chase
• Leptochloa virletii E.Fourn.
• Megastachya uninervia J.Presl
• Ottochloa malabarica (L.) Dandy
• Panicum malabaricum (L.) Merr.
• Poa contracta Retz.
• Poa fusca (L.) Desf.
• Poa malabarica L.
• Poa procera Roxb.
• Poa uninervia (J.Presl) Kunth
• Puccinellia carinata (Griseb.) Ponert
• Rabdochloa imbricata (Thurb.) Kuntze
• Syntherisma malabarica (L.) Sw. ex Roem. & Schult.
• Tridens capensis Nees
• Tridens duartei Catasús
• Tridens veralensis Catasús
• Tridens virens Nees
• Triodia ambigua R.Br.
• Triodia capensis (Nees) T.Durand & Schinz
• Triodia formosana Honda
• Triodia livida (Nees) T.Durand & Schinz
• Triodia parviflora R.Br.
• Uralepis alba Steud.
• Uralepis anderssonii Aresch.
• Uralepis capensis (Nees) Kunth
• Uralepis composita Buckley
• Uralepis drummondii Steud.
• Uralepis fusca (L.) Steud.
• Uralepis livida (Nees) Steud.
• Uralepis verticillata (Nees & Meyen) Steud.
• Uralepis virens (Nees) Kunth

International Common Names

• English: bearded sprangletop; beetle grass; brown beetle grass; littoral sprangletop; Malabar sprangletop; Mexican sprangletop; sprangletop; swamp grass
• Spanish: paja gris
• Chinese: shuang fu cao

Local Common Names

• Australia: diplanchne
• India: chamapullu

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

Leptochloa fusca is the latest of a very large number of names applied to this species. Originally known as Festuca fusca by Linnaeus, it has been included in Poa, Digitaria and numerous other genera, including Diplachne Peterson et al. (2012). Snow et al. (2018) make a strong case for use of the name Diplachne fusca and this is now used by USDA-ARS (2018), while most other authorities including The Plant List (2013) and USDA-NRCS (2018) continue to use Leptochloa fusca.  

The taxonomy of L. fusca is still uncertain and many botanical sources including The Plant List (2013), USDA-ARS (2018), WCSP (2018) and Missouri Botanical Garden (2018), recognize three subspecies: fascicularis, muelleri and uninervia, in addition to subsp. fusca, with differing distributions as described by Peterson et al. (2012) and Snow et al. (2018). These are all, at times, referred to as full species. The differing distributions are indicated to some degree in the distribution table, but for most purposes, the group is treated as a single species throughout this datasheet.

Perennial, loosely tufted to rhizomatous. Culms erect or geniculate and rooting from lower nodes, up to 100 cm or more tall. Leaf sheaths glabrous; leaf blades tough, usually involute, 5-30(-50) × 0.15-0.3(-0.6) cm, adaxial surface scabrid, abaxial surface subglabrous; ligule 3-12 mm, acute. Inflorescence 15-25 cm, scabrid; racemes 3-28, indistinctly unilateral, 4-20 cm, straight, ascending or spreading, spikelets usually distant. Spikelets glaucous-green, subterete, 6-14 mm, florets 5-12; glumes keeled; lower glume lanceolate, 2-3 mm, acute; upper glume narrowly oblong, 3-4 mm, acute or mucronate; lemmas narrowly oblong, dorsally sub-rounded, lowest 4-5 mm, lower lateral veins pilose, entire or 2-dentate, midvein often produced into a short 0.3-1.6 mm awn; palea ciliolate along upper keels. Callus laterally pilose. Anthers 0.5-0.75(-2.5) mm. Caryopsis elliptic-oblong, 1.5-2.5 mm, dorso-ventrally flattened (AusGrass2, 2015; Flora of China Editorial Committee, 2018).

The subspecies are separated as follows (Snow et al., 2018):

L. fusca subsp. muelleri: lemmas flat, relatively broad, to 2.0 mm wide; panicles narrow, mostly less than 5 cm wide; panicle branches generally steeply erect, often flexuous near tips; hairs on lateral nerves of lemma sericeous to velutinous, often densely so and typically becoming divaricate with age; lemma apices mostly broadly acute, awnless or sometimes mucronate; Australian interior.

L. fusca subsp. uninervia: lemma apices obtuse to truncate, usually notched and often mucronate; lemmas often dark green or lead colored; spikelets relatively short, 5–10 mm, anthers usually less than 0.7 mm; rachilla rarely visible during anthesis; mostly New World tropics. 

L. fusca subsp. fusca: lemma apices various, obtuse to acute or acuminate, notched or not; lemmas of various colors; spikelets 6–14 mm; anthers usually 0.5–2.7 mm; mostly Old World, southern South America, introduced into North America.

L. fusca subsp. fascicularis: lemmas slightly keeled, relatively narrow, mostly less than 1.5 mm wide; panicles somewhat broad, particularly at base, to 22 cm wide; panicle branches somewhat erect to reflexed, the branches not flexuous near tips; hairs on lateral nerves of sericeous, rarely densely so, typically remaining more or less appressed; lemma apices acute to acuminate, awnless or with awns to 3.5 mm long; mostly New World.

Leptochloa fusca subsp. uninervia and subsp. fascicularis are apparently recent introductions to Spain, where they were first recorded in 1990 (GBIF, 2014). In Australia, L. fusca subsp. uninervis was first recognized in 1999 (Snow and Simon, 1999). In Italy, L. fusca subsp. fascicularis was first reported in 2000 and was apparently introduced from Spain (Romani and Tabacchi, 2000). In the Canary islands, L. fusca subsp. uninervia was first recorded in a plant nursery in Gran Canaria in 2011 and it is spreading rapidly (Verloove, 2013). In St. Lucia, L. fusca subsp. fusca was apparently introduced as a seed contaminant on heavy equipment imported to be used at Praslin (Graveson, 2016). 

Soil drainage

• free
• seasonally waterlogged

Soil reaction

• acid
• alkaline
• neutral
• very acid
• very alkaline

Soil texture

• heavy
• light
• medium

Special soil tolerances

• infertile
• shallow

Leptochloafusca spreads predominantly by seed. Seeds are easily dispersed by water as the plants often grow in ditches and drains, on the edges of irrigation channels and along the margins of permanent rivers (Osca, 2013; Queensland Government, 2018). Seeds can be dispersed as contaminant in crop and pasture seeds, soil and machinery (Taberner et al. 2011). 

Leptochloa fusca is an important weed of rice fields (Osca, 2013). In India, this species was the most dominant weed species, occurring in approximately 85% of the sites surveyed (Vidya et al., 2004). It is also listed as a major weed of rice in Cuba (Colon and Antigua, 1989), Australia (McIntyre et al., 1989), South Korea (Kang and Shim, 2002), Senegal (Haefele et al., 2000), Spain (Osca, 2013) and USA (Carey et al., 1994). It is also one of the most common weeds in onion and tomato-green pepper plantations in Venezuela (Martínez et al., 2003).

Leptochloa fusca is an environmental weed that often can be found invading brackish water, salt marshes, irrigation ditches, riverbanks and along disturbed areas along roadsides and pastures (Flora of China Editorial Committee, 2018; PIER, 2018; USDA-NRCS, 2018). In Australia, Leptochloa fusca subsp. uninervia is regarded as an environmental weed threatening brackish, saline and freshwater wetlands (Queensland Government, 2018). Once established in these habitats it forms dense stands that outcompete native grasses, sedges and other wetland plants, replacing some species and affecting populations of waterbirds and other wildlife (Queensland Government, 2018). In Hawaii, it is also listed as an invasive species abundant around the margins of brackish water ponds, wet, disturbed places such as along irrigation ditches and in shallow, standing water (Wagner et al., 1999; PIER, 2018).

• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Long lived
• Has high reproductive potential
• Has propagules that can remain viable for more than one year
• Reproduces asexually

• Modification of fire regime
• Modification of hydrology
• Modification of nutrient regime
• Modification of successional patterns
• Monoculture formation
• Negatively impacts agriculture
• Reduced amenity values
• Reduced native biodiversity
• Threat to/ loss of native species

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

• Difficult to identify/detect in the field
• Difficult/costly to control

Leptochloa fusca is often planted for forage, green fodder and dry matter yields (Verma and Raghuwanshi, 2004). In Pakistan, it is cultivated on saline alkaline soil as a source of biomass. It has been also used for improvement of degraded and salt-affected soils (Akhter et al., 2004; Ahmad, 2010). Tawfik et al. (2013) suggested the potential of L. fusca as a biofuel in Egypt. 

Draft datasheet under review