Rottboellia cochinchinensis

Rottboellia cochinchinensis (Lour.) Clayton, Kew Bull. 35: 817 1981. (Syn: Aegilops fluviatilis Blanco; Manisuris exaltata Kuntze; Manisuris exaltata var. appendiculata (Steud.) Honda; Ophiuros appendiculatus Steud.; Rottboellia arundinacea Hochst. ex A.Rich.; Rottboellia denudata Steud.; Rottboellia exaltata var. appendiculata (Steud.) Hack.; Rottboellia exaltata f. arundinacea (Hochst. ex A.Rich.) Hack.; Rottboellia exaltata var. genuina Schweinf.; Rottboellia exaltata f. glaberrima Chiov.; Rottboellia exaltata var. robusta Hook.f.; Rottboellia hispida Roxb. ex Hook.f. [Invalid]; Rottboellia setosa J.Presl; Stegosia cochinchinensis Lour.; Stegosia exaltata (Kuntze) Nash);

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Tropical & Subtropical Old World to N. & NE. Australia: Andaman Is., Angola, Bangladesh, Benin, Botswana, Burkina, Burundi, Cameroon, Cape Verde, Central African Repu, Chad, China South-Central, China Southeast, Christmas I., Comoros, Congo, East Himalaya, Equatorial Guinea, Eritrea, Ethiopia, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Gulf of Guinea Is., Hainan, India, Ivory Coast, Jawa, Kenya, KwaZulu-Natal, Laos, Lesser Sunda Is., Liberia, Madagascar, Malawi, Malaya, Mali, Mauritius, Mozambique, Myanmar, Namibia, Nansei-shoto, New Guinea, Niger, Nigeria, Northern Provinces, Northern Territory, Oman, Philippines, Queensland, Réunion, Senegal, Seychelles, Sierra Leone, Solomon Is., Somalia, South China Sea, Sri Lanka, Sudan, Swaziland, Taiwan, Tanzania, Thailand, Togo, Uganda, Vietnam, West Himalaya, Yemen, Zambia, Zaïre, Zimbabwe; Introduced into: Alabama, Argentina Northwest, Arkansas, Bahamas, Belize, Bolivia, Brazil Southeast, Brazil West-Central, Cayman Is., Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, Florida, French Guiana, Galápagos, Georgia, Guatemala, Haiti, Honduras, Illinois, Indiana, Jamaica, Japan, Leeward Is., Louisiana, Mexico Central, Mexico Gulf, Mexico Southeast, Mexico Southwest, Mississippi, Nicaragua, North Carolina, Panamá, Peru, Puerto Rico, Samoa, Suriname, Texas, Trinidad-Tobago, Windward Is. as per POWO;
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grass ID2 from Hooghly 15/9/12 SK2:

Found this grass beside a railway platform, today. Could this be another Hemarthria species?

Species : UNKNOWN

Habit & Habitat : about 4 feet or more tall, a few even more than 5.5 feet; leaves = length more than 45 cm, leaf width 1.7 cm; inflorescence (?) avg. 15 cm.

Date : 15/9/12, 2.15 p.m.
Place : Begampur (Hooghly)

Received an ID suggestion that fits very well with this grass, Rottboellia cochinchinensis (Loureiro) Clayton –

description – http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=242414244
image – http://www.nature-museum.net/Share/DFS.=1
http://www.zimbabweflora.co.zw/speciesdata/image-display

I would like to add some more information relating to the place, Begampur, where i found this grass.

Like Dhaniakhali in Hooghly, Begampur is also known for its cotton SARI.
It is the birthplace of world famous painter Late Gobardhan Ash. I have a few prints of his paintings on Bengal famine. I also have the privilege of knowing his son Dr. Nirban Ash, also a painter himself, personally.
A nearby (2 km) place BARA-TAJPUR is birthplace of S. Wajid Ali, grandfather of Nafisa Ali.
And if i do not mistake champion powerlifter Ms Sumita Laha also comes from nearby place.

May be Hemarthria compressa De Silva,

I have a previous post of H. compressa at – https://groups.google.com/d/topic/indiantreepix/RS.
This grass looks slightly different. Does H. compressa has sub species or variants?

Yes. It is Rottboellia cochinchinensis also called Rottboellia exaltata. If you observe the lowest leaf sheaths, you can find stiff hairs, which also may sting or itch when touched. Hence, this is also called Itch grass.