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Panicum repens is a species of grass known by many common names, including torpedograss, creeping panic, panic rampant, couch panicum, wainaku grass, quack grass, dog-tooth grass, and bullet grass. Its exact native range is obscure. Sources suggest that the grass is native to “Africa and/or Asia”,[1] “Europe or Australia”,[2] “Eurasia”,[3] “Australia”,[4] “Europe, Asia, and Africa”,[5] or other specific regions, including the Mediterranean, Israel, and Argentina.[6] It is present in many places as an introduced species and often a noxious weed. It has been called “one of the world’s worst weeds.”[3]

This perennial grass spreads via its large, branching rhizomes, which are thick and pointed. The pointed shape of the rhizome tip gives the plant the name torpedograss. The rhizomes creep along the ground or float in water, forming floating mats. They can reach a length of 6 meters (20 ft) and a soil depth of 7 meters (23 ft), and they can form a mat 15 centimeters (5.9 in) thick. The spreading rhizomes sprout repeatedly to form colonies of stems.[6] The stems are 20 to 90 centimeters (7.9 to 35.4 in) tall,[7] sometimes reaching 1 meter (3 ft 3 in). They grow erect or bend down. The leaves are stiff and straight, linear in shape, and flat or folded. They are sometimes white in color and waxy in texture. The inflorescence is a loose panicle of branches bearing small spikelets 2 to 3 millimeters (0.079 to 0.118 in) long.[6][7]
The grass spreads primarily via its rhizome. It has been noted to grow 1.3 centimeters (0.51 in) in length per day. The stems and rhizomes also produce tillers. The rhizome can endure drying and flooding. Dry or wet conditions may reduce the amount of shoots produced by the rhizome, but they do not kill it. The rhizome can disperse when parts of it break off and drop onto the substrate elsewhere, anchoring and putting up new shoots. The plant survives and sprouts after herbicide application, grazing, cutting, plowing or disking, and burning. The grass rarely reproduces by seed.[6] It has been noted to reproduce by seed in Portugal,[8] but does not do so in the United States,[9] and it was described as “incapable of fruiting” in Japan. Seeds are sometimes observed but they are apparently rarely viable, with many studies describing zero germination.[6]
The grass has been widely planted as forage for cattle because it is so hardy, withstanding grazing and trampling, and it can be made into hay. However, it is not one of the more palatable or nutritious grasses. It is also good for erosion control because it binds the soil. Indeed, it is still recommended for planting along shorelines to stabilize them.[10]
(From Wikipedia on 12.11.14)

Perennials. Culms 30-75 cm long, erect or trailing, rhizomatous, rooting at the lower nodes; nodes glabrous. Leaves 7-24 x 0.4-0.7 cm, linear or linear-lanceolate, base shallowly cordate, apex acuminate, distichous, glaucous, scattered-pubescent on the upper surface; sheaths to 7 cm long, ciliate along the margins; ligules membranous, with dense tuft of hairs behind. Panicles 6-18 cm long. Spikelets 2.5-3.5 mm long, oblong-lanceolate, acute; pedicels 2-5 mm long. Lower glume c. 1 x 1.5 mm, ovate. Upper glume 2-3 x 1-1.5 mm, ovate-lanceolate, acute. Lower floret male. Upper floret bisexual. First lemma 2-3 x 1-1.5 mm, ovate-lanceolate. Palea c. 2.5 x 1 mm, oblong-lanceolate, hyaline, 2-keeled. Stamens 3. Second lemma 1.5-2. x 0.5-1 mm, oblong, subcoriaceous. Palea elliptic, subcoriaceous. Stamens 3. Ovary ovate; stigma c. 1 mm long.
Flowering and fruiting: July-September
Wetlands, marshy areas of grasslands and wastelands
Tropics and subtropics of both hemispheres
(Attributions- Dr. N Sasidharan (Dr. B P Pal Fellow), Kerala Forest Research Institute, Peechi from India Biodiversity Portal)

Panicum repens L. SN Nov03 : 1 post by 1 author. Attachments (3)
Panicum repens L., an hardy grass near moist places, leaves slightly broader, buffalo likes very much.

ID KANNUR 11 : 5 posts by 2 authors. Attachments (3)
Please identify this grass from the riparian zone of Kannur District of Kerala.

Spikelets are not cleared. but seems to be Panicum sp.

Panicum repens