Fact Sheets

FICHES DE
RENSEIGNEMENTS

Cynodon dactylon (L.) Pers. var. dactylon

Family :

Famille :

Poaceae

Synonym(s) :

Synonyme(s) :

Panicum dactylon L. (USDA-ARS-NPGS 2023)

Common Name(s) :

Nom(s) commun(s) :

Bermudagrass

(English) (Wiersema and Léon 1999; AOSA 2023; USDA-AMS 2023a; USDA-ARS-NPGS 2023)

Bahama grass (English) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Devil’s grass (English) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Hariali grass (English) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Quick grass (English) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Kweekgras (Afrikaans) (USDA-ARS-NPGS 2023)

Chiendent pied-de-poule (French) (USDA-ARS-NPGS 2023)

Cynodon dactyle (French) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Grand chiendent (French) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Bermudagras (German) (USDA-ARS-NPGS 2023)

Hundezahngras (Germany) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Dhub (India) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Doob (India) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Gramina (Italian) (ISTA 1982)

Capim-Bermuda (Portuguese) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Grama rastrera (Spanish) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Zacate de Bermuda (Spanish) (Wiersema and Léon 1999; USDA-ARS-NPGS 2023)

Gou yan gen (yuan bian zhong) [狗牙根 (原变种)Chinese] (efloras 2023)

  • Bermuda grass (Cynodon dactylon) florets and caryopsis

  • Bermuda grass (Cynodon dactylon) caryopses

  • Bermuda grass (Cynodon dactylon) caryopsis

  • Bermuda grass (Cynodon dactylon) caryopsis

Explore More :

Explore plus :

Overview

Aperçu

Regulation :

Remarques Réglementation:

  • USA Federal Noxious Weed Seed List

Regulation Notes:

  • Cynodon dactylon var. dactylon, C. d. var. aridus, and Cynodon spp. are classified as noxious weed seeds or restricted undesirable grass seeds in various US states and in the District of Columbia, USA (USDA-AMS 2023b).

Distribution :

Répartition :

Cynodon dactylon var. dactylon is a highly variable warm season perennial grass that is believed to have originated in Africa (Rojas-Sandoval and Acevedo-Rodríguez 2014). It now occurs worldwide in tropical and subtropical regions of North, Central, and South America, Asia, Pacific islands, Caribbean islands, and in temperate areas of North America and Europe except where prolonged winter frost is detrimental to its survival (Rojas-Sandoval and Acevedo-Rodríguez 2014).

Habitat and Crop Association :

Habitat et Cultures Associées :

Cynodon dactylon var. dactylon is a cosmopolitan weed that can invade annual and perennial crops, orchards, turf, pastures, urban landscapes, forestry areas, fallow fields, and other disturbed areas (DiTomaso and Healy 2007; Rojas-Sandoval and Acevedo-Rodríguez 2014). Weedy C. dactylon var. dactylon impacts many crops in the subtropics including Gossypium hirsutum (cotton), Saccharum officinarum (sugarcane), Nicotiana tabacum (tobacco), vegetables and fruit trees (Rojas-Sandoval and Acevedo-Rodríguez 2014). Once established it can be difficult to eradicate (Barkworth et al. 2003).

This hardy plant can be found in areas below sea level in the Jordan rift and in North Africa, to elevations above 3000 m in Nepal, and at latitudes approaching 53°N (Harlan and de Wet 1969) where it is only limited by its sensitivity to hard frost conditions (Rojas-Sandoval and Acevedo-Rodríguez 2014). This species prefers medium to heavy, moist, well-drained soils, but will grow on a wide variety of acid, alkaline, or saline soils, and undisturbed rhizomes can survive prolonged periods of flooding or drought (DiTomaso and Healy 2007; Rojas-Sandoval and Acevedo-Rodríguez 2014).

Economic Use, cultivation area, and Weed Association :

Utilisation économique, zone de culture et association de mauvaises herbes :

Cynodon dactylon var. dactylon has undergone extensive research and breeding to develop a multitude of cultivars for a variety of uses. There are currently 222 cultivars of C. dactylon registered with the United States Department of Agriculture (USDA-AMS 2023c). Cultivars have been developed for establishing perennial pastures, hay production, and livestock feed (Alderson and Sharp 1995; Redfearn and Rice 2017). Cultivars have also been developed for lawns, parks, playgrounds, athletic fields, golf courses, erosion control and reclamation. These cultivars can tolerate high traffic, high temperatures, minimal watering, mowing, and close mowing for golf course putting greens (Alderson and Sharp 1995).

In the United States there are seed and vegetative propagation standards in place for C. dactylon cultivar certification (OCIA 2017; AOSCA 2023). Propagation of commercially available cultivars may be by seed or by vegetative means or both (Alderson and Sharp 1995).

Under full or partial sun, turf type C. dactylon can produce relatively weed-free, low maintenance, traffic-resistant ground covers (USDA-NRCS 2020). However, in pastures major weed species association with C. dactylon include Cenchrus echinatus L. (southern sandbur), Cenchrus longispinus (Hack.) Fernald (longspine or mat sandbur), and Cenchrus spinifex Cav. (field or coast sandbur) (Rocateli and Post 2016). Cenchrus species (sandburs) present a problem for palatability because the spiny seed heads can injure the mouths of grazing livestock (DiTomaso and Healy 2007; Rocateli and Post 2016). Solanum carolinense L. (horsenettle) and S. c. var. floridanum (Shuttlw. Ex Dunal) Chapm. (Florida horsenettle) are problematic species in C. dactylon pastures in the southeastern United States because the foliage and fruits are toxic to livestock (Nichols et al. 1992; DiTomaso and Healy 2007).

Duration of Life Cycle :

Durée du cycle vital:

Perennial

Dispersal Unit Type :

Type d’unité de dispersion :

Floret and caryopsis

General Information

RENSEIGNEMENTS GÉNÉRAUX

Cynodon dactylon var. dactylon is a highly variable perennial C4 grass widely grown in many tropical and warm temperate regions of the world (DiTomaso and Healy 2007). Hundreds of cultivars have been developed for a wide range of uses, such as durable turf for lawns, athletic fields, golf courses, soil stabilization, wildlife forage, livestock pasture, and hay (Alderson and Sharp 1995; USDA-AMS 2023c; USDA-NRCS 2020).

Plants can rapidly colonize new areas via seeds or rhizome and stolon fragments forming dense mats (DiTomaso and Healy 2007; Rojas-Sandoval and Acevedo-Rodríguez 2014). Due to a vigorous creeping habit, and the ability to quickly recover after fire, tolerate flooding, and prolonged drought, C. d. var. dactylon has become a significant weed pest in many places around the world (Rojas-Sandoval and Acevedo-Rodríguez 2014).

Unintentional dispersal of seeds or stolon and rhizome fragments can occur by flooding, irrigation, contaminated agricultural and landscape maintenance equipment, movement of hay bales, and by animals ingesting and passing the seeds in manure (Di Tomaso and Healy 2007; Rojas-Sandoval and Acevedo-Rodríguez 2014). Seeds can also be spread as contaminants in commercial seed lots of agricultural and vegetable seeds.

Sensitive individuals may develop dermatitis following contact with the plants and C. dactylon pollen is a common cause of hay fever (Fuller and McClintock 1986). In the United States, reports of photosensitization, neurological problems, and symptoms of mold or fungal toxicity have occurred in cattle grazing on C. dactylon. (Fuller and McClintock 1986; Di Tomaso and Healy 2007).

Cynodon dactylon is listed as invasive in Australia, Indonesia, Singapore, Cambodia, Vietnam, Mexico, Costa Rica, Puerto Rico, Chile, Colombia, Uruguay, Argentina, Brazil, on many Pacific islands, and elsewhere (Rojas-Sandoval and Acevedo-Rodríguez 2014). It is also classified as a noxious weed seed in many US states (USDA-AMS 2023b). As an invasive plant, C. dactylon has the potential to diminish crop yield by out competing crop plants, to increase cost of crop production (e.g., herbicides, manual labor), and to threaten native species by competing for resources, strangling native plants, and altering plant community composition (Rojas-Sandoval and Acevedo-Rodríguez 2014).

The species C. dactylon is divided into six botanical varieties (Harlan and de Wet 1969). In addition to C. d. var. dactylon, the five other botanical varieties include:

C.d. var. afghanicus J. R. Harlan & de Wet plants are similar to other botanical varieties of C. dactylon except they do not produce rhizomes or produce only very short rhizome-like structures at the crown of the plant (Harlan and de Wet 1969). This variety is limited in known distribution to the steppes of Afghanistan (de Wet and Harlan 1970; USDA-ARS-NPGS 2023).

C. d. var. aridus Harland & de Wet (giant bermudagrass; USDA-ARS-NPGS 2023) is described as a large, robust plant, blueish-green in colour, producing deep and fast spreading rhizomes, as well as developing remarkably long, slender, and fast-growing stolons with leafy tips (Harlan and de Wet 1969), and lacking pubescence (Alderson and Sharp 1995). This variety is native to South Africa, Zambia, Tanzania, Israel, India, and Sri Lanka (USDA-ARS-NPGS 2023). Its introduction and spread are limited elsewhere (Harlan and de Wet 1969). Seeds of this variety are commercially available and are sometimes sold in mixtures with seeds of C. d. var. dactylon. This variety is used for fodder, forage, erosion control, lawn, and turf (Markle et al. 1998).

C. d. var. coursii (A. Camus) J. R. Harlan & de Wet does not produce rhizomes, the robust stolons and stems produce plants 40 to 50 cm tall, leaves on the upper stems are pressed tightly against the stem and are bunched at the tip (Harlan and de Wet 1969; de Wet and Harlan 1970). This variety is endemic to the highlands of Madagascar (Harlan and de Wet 1969).

C. d. var. elegans Rendle plants are described as rhizomatous, forming a loose mat of stems lying on the ground or rising in an arc, tips of the stolons are scaly, and plants are green in colour (Harlan and de Wet 1969). This variety is native to Angola, Mozambique, Zambia, Zimbabwe, Namibia, and South Africa (USDA-ARS-NPGS 2023).

C. d. var. polevansii (Stent) J. R. Harlan & de Wet plants are dark green coloured, the stolons are branched with short internodes that form a dense turf with stiff upright leaves (Harlan and de Wet 1969). This variety is endemic to saline areas in the North-West Province of South Africa (Harlan and de Wet 1969; de Wet and Harlan 1970).

Cynodon dactylon var. dactylon can hybridize, either naturally or experimentally, with other botanical varieties of C. dactylon and other Cynodon species (Harlan and de Wet 1969; de Wet and Harlan 1970).

.

Identification

Identification

<
>
  • Spikelet

    Size

    • Spikelet length: 2 – 3.2 mm (Barkworth et al. 2003).
    • Lower (1st) glume length: 1.5 – 2 mm (Barkworth et al. 2003).
    • Upper (2nd) glume length: 1.4 – 2.3 mm (Barkworth et al. 2003).
    • Glume shorter than the floret.

    Shape

    • Spikelet laterally compressed; egg-shaped to D-shaped.
    • Glumes strongly keeled.

    Surface Texture

    • Spikelet surface smooth and shiny.
    • Glumes membranous.

    Colour

    • Spikelet light brownish yellow, sometimes purple tinged.

    Other Features

    • The spikelet usually contains a single fertile floret, additional smaller sterile floret(s) may develop above the fertile floret.
    • Spikelet disarticulation usually occurs above the glumes (the glumes usually remain attached to the plant but may occasionally remain attached to the fertile floret).
  • Floret

    Size

    • Floret length*: 1.7 – 2.2 mm (average 2 mm); width (in palea view)*: 0.5 – 0.6 mm (average 0.55 mm); thickness (in lateral view)*: 0.7 – 0.9 mm (average 0.8 mm).
    • Palea about equal to lemma length.
    • Rachilla about one-half the length of the floret.
    *Note: minimum and maximum based on a random selection of 10 florets in normal range of this species using image measurement protocol (ISMA 2020). CDA-S-22612

    Floret size measurements from the literature:
    Lemma length 1.9 – 3.1 mm (Barkworth et al. 2003)
    Floret length 2 mm, width 0.75 – 1 mm (Musil 1963).
    Floret length 2.3 – 2.7 mm; width 1 – 1.2 mm (Bojňanský and Fargašová 2007).

    Shape

    • Floret laterally compressed, egg-shaped to D-shaped in lateral view.
    • Lemma strongly keeled.
    • Palea keeled.
    • Callus blunt.

    Surface Texture

    • Surface smooth and shiny, unmilled florets with hairs on margins.
    • Lemma tough and firm but flexible (cartilaginous).
    • Lemma 3-veined, with or without hairs on keel in upper half.
    • Palea 2-veined.
    • Palea and callus smooth.

    Colour

    • Floret light brownish-yellow, sometimes purple tinged.
  • Caryopsis

    Size

    • Caryopsis length*: 1.1 – 1.4 mm (average 1.3 mm); width (embryo view)*: 0.4 – 0.5 mm (average 0.45 mm); thickness (lateral view)*: 0.6 – 0.7 mm (average 0.6 mm).
    *Note: minimum and maximum based on a random selection of 10 caryopses in normal range of this species using image measurement protocol (ISMA 2020). CDA-S-22612

    Additional caryopsis measurements from the literature:
    Caryopsis length: 1.1 – 1.3 mm; width 0.6 – 0.8 mm (Bojňanský and Fargašová 2007).

    Shape

    • Caryopsis laterally compressed, oval shaped in lateral view and teardrop shaped in embryo view.
    • Caryopsis end opposite the embryo is usually rounded or may have a small bump of the remnant style base.

    Surface Texture

    • Caryopsis surface, smooth to minutely striate.

    Colour

    • Caryopsis colour yellow to light reddish-brown.
    • Caryopsis dull to lustrous, yellowish coloured, and semi-translucent when viewed over a diaphanoscope (Musil 1963).

    Other Features

    • Hilum round, located near base of caryopsis on side opposite the embryo.
<
>
<
>
  • Embryo

    Size

    • Embryo length*: 0.5 – 0.7 mm (average 0.6 mm).
    • Embryo is about one-half the length of caryopsis.
    *Note: minimum and maximum based on a random selection of 10 embryos in normal range of this species using image measurement protocol (ISMA 2020). CDA-S-22612

    Shape

    • Embryo shape oval.

    Endosperm

    • Endosperm solid (Terrell 1971).

    Other Features

    • Embryo in lateral position (Martin 1946).

Identification Tips

CONSEILS POUR L’IDENTIFICATION

Species of Cynodon have laterally compressed, strongly keeled, and usually D-shaped florets (rarely egg-shaped), the rachilla is slender and bristle-like and is about one-half the length of the palea. The spikelets usually have one floret but if more are present they are sterile and highly reduced in size. The floret usually separates from the spikelet above the glumes, but occasionally the glumes may stay attached. The morphological differences among species of Cynodon are mostly of vegetative structures, growth habit, and inflorescence structure (deWet and Harlan 1970).

Additional Botany Information

AUTRES RENSEIGNEMENTS BOTANIQUES

Flowers/Inflorescence

  • The panicle inflorescence forms at the tip of the stem and consists of several finger-like branches extending from a common point (digitate or hand-like), each branch is 2 – 6 cm long, with overlapping, nearly sessile, laterally compressed spikelets arranged in two rows on one side of each branch (Barkworth et al. 2003).

Vegetative Features

  • Plants produce both rhizomes and branched stolons that develop fibrous roots or new plants at the nodes (Barkworth et al. 2003).
  • Rhizome and stolon fragments can readily produce new plants (DiTomaso and Healy 2007).
  • Stems 5 – 50 cm long (Barkworth et al. 2003), forming loose uneven patches to very dense turf.
  • Leaves may be coarse or fine, hairy or glabrous; leaf colour can range from light blue-green to dark green during the growing season, and turn brown as the plants go dormant when average daytime temperatures dip below 10°C or nighttime temperatures fall below freezing (Harlan and deWet 1969; Barkworth et al. 2003; DiTomaso and Healy 2007).

Similar Species

ESPÈCES SEMBLABLES

Similar species are based on a study of seed morphology of various species, and those with similar dispersal units are identified. The study is limited by physical specimen and literature availability at the time of examination, and possibly impacted by the subjectivity of the authors based on their knowledge and experience. Providing similar species information for seed identification is to make users aware of similarities that could possibly result in misidentification.

The most likely type of similar Cynodon to be encountered in commercial seed trade:

Cynodon dactylon var. aridis J. R. Harlan & de Wet giant bermudagrass (AOSA 2023; USDA-AMS 2023a; USDA-ARS-NPGS 2023)

Florets 2.5 mm long and 1 mm wide, light brownish-yellow coloured and often purplish tinged; caryopsis about 1.5 mm long and 1 mm wide, dark grayish brown, dull, with coarse longitudinal striations, the end opposite the embryo is usually tapers to a point; when viewed over a diaphanoscope the caryopses are either opaque or semi-translucent and reddish coloured (Musil 1963). The morphological differences between C. d. var. dactylon and C. d. var. aridus dispersal units are minimal and separation is primarily based on the shape and color of the caryopses although this type of separation is not entirely reliable.

Click to select species

Cliquez pour sélectionner les espèces

Comparison Window

Fenêtre de comparaison

Need ID Help?

Besoin d’aide pour l’identification?

Reference(s)

Référence(s)

Alderson, J. & W. C. Sharp. 1995. Grass Varieties in the United States, USDA Agric. Handbook 170, rev. ed. CRC Press.

Association of Official Seed Analysts (AOSA). 2023. Rules for Testing Seeds, Vol. 3: Uniform Classification of Weed and Crop Seeds. Association of Official Seed Analysts, Wichita, KS, USA.

Association of Official Seed Certifying Agencies (AOSCA). 2023. AOSCA Grass and Grass VFL Variety Review Board. https://aosca.org/programs-services/national-variety-review-boards/grass/ Accessed December 14, 2023.

Barkworth, M. E., Capels, K. M., Long, S., and Piep, M. B. 2003. Flora of North America, Vol. 25 Magnoliophyta: Commelinidae (in part): Poaceae, part 2. Oxford University Press.

Bojňanský, V. and Fargašová, A. 2007. Atlas of Seeds and Fruits of Central and East-European Flora: The Carpathian Mountains Region. Springer, Dordrecht, The Netherlands.

de Wet, J. M. J. and J. R. Harlan. 1970. Biosystematics of Cynodon L. C. Rich. (Gramineae). Taxon 19(4):565-569.

DiTomaso, J. M. and Healy, E. A. 2007. Weeds of California and Other Western States. Vol. 2: Geraniaceae – Zygophyllaceae. Agriculture and Natural Resources Publication 3488. University of California, Oakland, CA.

eFloras. 2023. Flora of China: Cynodon dactylon var. dactylon http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=242316424  Accessed December 13, 2023.

Fuller, T. C. and McClintock, E. 1986. Poisonous Plants of California. University of California Press, Berkeley, CA.

Harlan, J. R. and de Wet, J. M. J. 1969. Sources of variation in Cynodon dactylon (L.) Pers. Crop Sci. 9(6):774-778.

International Seed Morphology Association (ISMA). 2020. Method for seed size measurement. Version 1.0. ISMA Publication Guide. https://www.idseed.org/authors/details/method_for_seed_size_measurement.html.

International Seed Testing Association. 1982. A Multilingual Glossary of Common Plant-Names 1. Field crops, grasses and vegetables, ed. 2.

Markle, G. M., Baron, J. J., Schneider, B. A., and Moses, L. 1998. Food and Feed Crops of the United States. 2nd Ed. Meisler Pub Co.

Martin, A. C. 1946. The comparative internal morphology of seeds. The American Midland Naturalist 36(3):513-660.

Musil, A. F. 1963. Identification of Crop and Weed Seeds. Agriculture Handbook No. 219. U. S. Department of Agriculture. Washington, D.C.

Nichols, R. L., Cardina, J., Lynch, R. L., Minton, N. A. and Wells, H. D. 1992. Insects, nematodes, and pathogens associated with horsenettle (Solanum carolinense) in bermudagrass (Cynodon dactylon) pastures. Weed Sci. 40(2):320-325.

Oklahoma Crop Improvement Association (OCIA). 2017. Specific Crop Standards Table of Contents. http://okcrop.okstate.edu/standards/specific-crop-standards/crabgrassUPDATED%20CERT%20STANDARDS%20-%20REVISED%202-12-17-1.pdf

Redfearn, D. and Rice, C. 2017. Bermudagrass Pasture Management. Oklahoma State University Extension. https://extension.okstate.edu/fact-sheets/bermudagrass-pasture-management.html.  Accessed December 14, 2023.

Rocateli, A. and Post, A. 2016. Sandbur control in bermudagrass pasture. Oklahoma State University Extension. https://extension.okstate.edu/fact-sheets/sandbur-control-in-bermudagrass-pasture.html.  Accessed December 14, 2023.

Rojas-Sandoval, J. and Acevedo-Rodríguez, P. 2014. Cynodon dactylon (Bermuda grass) – Datasheet. CABI Compendium. https://doi.org/10.1079/cabicompendium.17463  Accessed December 11, 2023.

Terrell, E. E. 1971. Survey of occurrences of liquid or soft endosperm in grass genera. Bull. Torr. Botan. Club 98(5):264-268.

United States Department of Agriculture-Agricultural Marketing Service (USDA-AMS). 2023a. Federal Seed Act Regulations. https://www.ecfr.gov/current/title-7/subtitle-B/chapter-I/subchapter-K/part-201?toc=1  Accessed December 13, 2023.

United States Department of Agriculture-Agricultural Marketing Service (USDA-AMS). 2023b. State Noxious-Weed Seed Requirements Recognized in the Administration of the Federal Seed Act. https://www.ams.usda.gov/sites/default/files/media/StateNoxiousWeedsSeedList.pdf  Accessed December 13, 2023.

United States Department of Agriculture-Agricultural Marketing Service (USDA-AMS). 2023c. Seed Variety Name Clearance Service. https://www.ams.usda.gov/services/seed-testing/applying-for-variety  Accessed December 14, 2023.

United States Department of Agriculture-Agricultural Research Service-National Plant Germplasm System (USDA-ARS-NPGS). 2023. Germplasm Resources Information Network (GRIN Taxonomy). National Germplasm Resources Laboratory, Beltsville, Maryland. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomydetail?id=315474  Accessed December 13, 2023.

United States Department of Agriculture-Natural Resources Conservation Service (USDA-NRCS). 2020. Bermudagrass, Cynodon dactylon (L.) Pers. Plant Fact Sheet. https://plants.usda.gov/DocumentLibrary/factsheet/pdf/fs_cyda.pdf  Accessed December 13, 2023.

Wiersema, J. H. and León, B. 1999. World Economic Plants: A Standard Reference. CRC Press, Boca Raton, FL.

Author(s)

AUTEUR(S)

Deborah J. Lionakis Meyer, California Department of Food and Agriculture (retired)

Acknowledgments

The author wishes to thank the following from the Canadian Food Inspection Agency (CFIA): reviewers Jennifer Neudorf and Angela Salzl for their suggestions for fact sheet improvement and Krishan Shah, former student, for his assistance with literature search and summary.