Family • Gramineae - Imperata cylindrica (Linn.) Beauv. var. Koenigii (Retz.) Benth. - SPEARGRASS - Mao Ken

Scientific names

Imperata cylindrica (L.) Beauv.
Imperata arundinacea Cirillo
Imperata koenigii (Retzius) P. Beauv.
Lagunus cylindricus (L.)
Saccharum koenigii Retz.
Da bai mao (Chin.)

Common names

Buchid (Iv.)
Bulum (If.)
Kogon (Tag.)
Gocon, gogon (Bik.)
Gaon (Ig.)
Goon (Bon.)
Ilib (Pamp.)
Panaw, pan-au (Ilk.)
Parang (Sulu)
Cogon grass (Engl.)
Wooly grass (Engl.)
Speargrass (Engl.)
Mao Ken (Chin.)

Other vernacular names

FRENCH: Herbe a paillote, Imperata cylindrique.
GERMAN: Alang-alang gras.
HINDI: Dabh, Darbha, Ulu.
ITALIAN: Falasco bianco.
JAPANESE: Chigaya, Fushige chigaya.
LAOTIAN: Nha kha.
MALAY: Elalangi, Lalang.
MALAYALAM: Darbha, Darbhappullu.
POLISH: Imperate cylindryczna.
SANSKRIT: Balbajamu, Darbha, Darbhah, Dharbai.
SPANISH: Carrizo.
THAI: La lae, La lang, Ya kha.

Gen info
Speargrass is one of the most dominant and noxious weeds in agricultural and non-agricultural fields. It is a prolific seed producer, when detached from stalks the seeds are carried by wind at long distances, and difficult to eradicate because of persistent rhizomes. It is ranked as the world’s seventh worse weed. In Nigeria, it is reported to have the potential to invade 260 million hectares of land.


Additional Sources and Suggested Readings

(1) Comparative anti-hyperglycemic potentials of medicinal plants / Villasenor I M and Lamadrid M R / J Ethnopharmacol. 2006 Mar 8;104(1-2):129-31. Epub 2005 Oct 25.

(2) Neuroprotective 2-(2-Phenylethyl) chromones of Imperata cylindrica / Jeong Seon Yoon et al / J. Nat. Prod., 2006, 69 (2), pp 290–291 • DOI: 10.1021/np0503808

(3) Graminone B, a Novel Lignan with Vasodilative Activity from Imperata cylindrica 

(4) Studies on the individual and combined diuretic effects of four Vietnamese traditional herbal remedies (Zea mays, Imperata cylindrica, Plantago major and Orthosiphon stamineus) / Doan Du Dat et al / Journal of ethnopharmacology / 1992, vol. 36, no3, pp. 225-231

(5) Graminone B, a novel lignan with vasodilative activity from Imperata cylindrica / Journal of Natural Products / Vol 57, No 12, pp 1734-1736, Dec 1994.

(6) Chemical Composition and Hepato-protective activity of Imperata cylindrica Beauv / Gamal A. Mohamed et al / RESEARCH ARTICLE, 2009 | Volume : 5 | Issue : 17 | Page : 28-36

(7) Diuretic effects of selected Thai indigenous medicinal plants in rats / Bungom Sripanidkulchai et al / Journal of Ethnopharmacology, Vol 75, Issues 2-3, May 2001, Pages 185-190 / doi:10.1016/S0378-8741(01)00173-8

(8) Sorting Imperata names / Authorised by Prof. Snow Barlow / Maintained by: Michel H. Porcher / MULTILINGUAL MULTISCRIPT PLANT NAME DATABASE / Copyright © 1997 – 2000 The University of Melbourne.

Kogon is an annual, erect, tufted grass, 30 to 80 centimeters high with a prominent underground stem. Rhizomes are much extended, equally noded and white. Stems are solid, rather slender; nodes glabrous or bearded. Leaves are flat, linear-lanceolate, 20 to 50 centimeters long, and 5 to 9 millimeters wide, stiff with scabrous margins. Flowers are in panicles, exserted, dense, subcylindric, white, 10 to 20 centimeters long, 5 to 15 centimeters in diameter, silvery-silky. Callus hairs copious, about twice as long as the glumes. Spikelets 1- to 2-flowered, 2 to 4 millimeters long, in pairs, its axis continuous. Stamens 1 or 2, anthers large.

– Throughout the Philippines, in open, rather dry lands, often forming extensive cogon grasslands called cogonales, ascending to 2,300 meters in altitude.
– Propagated through the stoloniferous rhizome or the downy caryopsis (fruits) from a mature spike.
– Also found in tropical Asia and Africa to Australia and Polynesia.


– Study isolated a new lignan glycoside, impecyloside, from the rhizome.
– Rhizomes have yielded arundoin, cylindrin, fernenol, cylindol, cylindrene, grminones and imperanene.

– Sweet tasting.
– Considered antifebrile, anthelmintic, antibacterial, diuretic, febrifuge, restorative, styptic, tonic.

Parts used and preparation
– Spikes and roots.
– Collect the underground portion, remove the roots, and clean.
– Cut into pieces. Fry with a strong fire until the covering turns yellow, sprinkle with clean water and sun-dry.
– The inflorescence may also be collected and sun-dried for use.


· In many Tagalog provinces, decoction of fresh roots used for dysentery.
· Decoction of fruiting spikes used as vulnerary; used as sedative when taken internally.
· Decoction used as blood purifier and as diuretic.
· For hemoptysis, hematuria, and nose bleeding (epistaxis): a decoction of 30 to 60 gms of the herb.
· For urinary tract infections: drink a decoction of 80 to 120 gms of fresh rhizomes.
· Painful outgrowth at the tongue. Use 30 to 90 gms dried rhizome, or 60 to 120 gms of fresh rhizome in decoction.
· Has also been used for diabetes, wound healing, arthritis.
· Root used in the treatment of nose bleeds, hematuria, edema.
· Decoction of root as anthelmintic.
· Decoction of fruiting spikes used as vulnerary; taken internally, as sedative.
· Decoction used as blood purifier and diuretic.
· In Chinese medicine, used as a diuretic and antiinflammatory. Also, runners used to make restorative, haemostatic and antifebrile medications.

· Paper-making.

Study Findings
• No Glucose Lowering: Comparative anti-hyperglycemic potentials of medicinal plants: Roots of IC has had folkloric use as an antidiabetic agent. The study showed no significant lowering in blood glucose levels with Imperata cylindrica.
• Neuroprotective: Neuroprotective 2-(2-Phenylethyl) chromones of Imperata cylindrica: Study yielded four compounds, two of which showed significant neuroprotective activity against glutamate-induced neurotoxicity
• Immunomodulating activity: Isolation and partial characterization of immunostimulating polysaccharides from Imperata cylindrica. Crude extract and some of the purified polysaccharides enhance the proliferation of murine splenocytes.
• Anti-Platelet Aggregation: Antiplatelet Aggregating Activity of Extracts of Indonesian Medicinal Plants: All eight Indonesian medicinal plants, including Imperata cylindrica, studied showed inhibitory effects on platelet aggregation.
• No Diuretic Effect: Study assessed the diuretic effect of four traditional Vietnamese herbal remedies – Zea mays, Imperata cylindrica, Plantago major and Orthosiphon stamineus. The study failed to show any effect on urine output and sodium excretion and indicates the need for critical reviews on the recommendations of empiric traditional use of plant materials. In a study on treatment of dysuria and diuretic effects of five indigenous Thai medicinal plants, the rhizome of IC apparently inhibited the urination of rats.
• Vasodilative Effect: The study yielded two novel lignans, graminones A and B. Graminone B showed inhibitory activity on the contraction of the rabbit aorta.
• Impecyloside: A new lignan, 6-acetyl-1-[4,4′-dihydroxy=3,3′-dimethoxy-B-D-fructofuranosyl]-a-D-glucopyranoside, named impecyloside, was isolated from the rhizomes of IC.
• Toxicity Studies: Study suggests the water extract of Imperata cylindrica does not cause acute and subchronic toxicities in rats.
• Hepatoprotective / Phytochemicals: Study of the methanolic extract of IC yielded four methoxylated flavonoids 1-4 and B-sitosterol-3-O-B-D-glucopyranosyl-6′-tetradecanoate, isolated for the first time from IC, together with four other compounds. Results showed a significant hepatoprotective activity on co-administration of ME of IC with CCl4.
• Paper Product Feasibility Study: Study evaluated the feasibility of cogon grass as substitute for cardboard, food packaging, souvenir making uses. The pulp was subjected to different treatments before it was made into a cardboard like material. Treatment C, with 5% water and 7.5% starch showed to be the best treatment.
• Uric Acid Lowering: Study evaluating the uric acid (C5H4N4)4) lowering potential of cogon grass showed no hypouricemic effect.