Persicaria posumbu (Buch.-Ham. ex D. Don) H. Gross, L. E. T. Loesener, Beih. Bot. Centralbl., Abt. 2, 37(2):113. 1919 (Syn: (=) Persicaria cespitosum (Blume) Nakai; (=) Polygonum cespitosum Blume; (≡) Polygonum posumbu Buch.-Ham. ex D. Don (basionym)) as per GRIN;
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Himalaya to Russian Far East and Philippines: Assam, Bangladesh, China North-Central, China South-Central, China Southeast, East Himalaya, Hainan, Japan, Korea, Kuril Is., Laos, Malaya, Manchuria, Myanmar, Nepal, Philippines, Primorye, Taiwan, Thailand, Tibet, Vietnam, West Himalaya as per POWO;
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Persicaria posumbu subsp. posumbu (syn: Persicaria caespitosa (Bl.) Nakai; Persicaria posumbu (Buch-Ham. ex D. Don) Nakai; Persicaria posumbu var. albiflora Iwata; Persicaria posumbu var. laxiflora (Meisn.) H.Hara; Persicaria yokusaiana (Makino) Nakai; Persicaria yokusaiana var. laxiflora (Meisn.) H.Hara; Persicaria yokusaianum Makino; Polygonum caespitosum Bl.; Polygonum caespitosum var. laxiflorum Meisn.; Polygonum caespitosum subsp. yokusaianum (Makino) Danser; Polygonum decumbens De Bruyn; Polygonum donii Wall.; Polygonum gracile Herb. Ham. ex Hook. fil.;  Polygonum posumbu Buch.-Ham. ex D. Don; Polygonum posumbu f. albiflorum (Iwata) G. Murata; Polygonum procumbens De Bruyn; Polygonum rhizocaulon De Bruyn; Polygonum yokusaianum Makino) as per Catalogue of Life
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North Korea, South Korea, Japan (Hokkaido, Honshu, Shikoku, Kyushu), Ryukyu Isl., China (Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shaanxi, Shandong, Sichuan, Yunnan, Zhejiang), Taiwan, Tibet, India, Indonesia, Philippines (Luzon, Mindanao), Nepal, Georgia [Caucasus] (introduced), Russian Far East, Nicobars (Great Nicobar Isl., Little Nicobar Isl.), Vietnam, Bhutan, Sikkim, ?Jammu & Kashmir, USA (introduced) (Pennsylvania (introduced)) as per Catalogue of Life
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ID No. 29042011 RD16:
Please help me to know this small herb
Date/Time-09/04/2011- 09 AM
Location- Place, Altitude, GPS-  Assam,
Habitat- Garden/ Urban/ Wild/ Type- Wild Type
Plant Habit- Tree/ Shrub/ Climber/ Herb-  Common herb
Leaves Type/ Shape/ Size- Leaf
Inflorescence Type/ Size- as seen in the photos
Flowers Size/ Colour/ Calyx/ Bracts- White,
Fruits Type/ Shape/ Size Seeds- Not seen

I hope Persicaria posumbu


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SK1105 24 APR-2018 : 9 posts by 3 authors. Attachments (8)
Location:  Godawari, Nepal  
Date: 18 April 2018
Altitude: 5000 ft.
Habit: Wild 

I am not able to conclude anything with these photographs. Looks close to Persicaria caespitosa, but not sure.


I think your guess matching.
The Plant List says no synonym whereas the Catalogue of life says some synonyms.
Request for the final validation.

Thanks, … for sharing the links. I would suggest you dissect the specimen if you have one. Persicaria is a complicated genus and hybridization is also frequent.
Your plant is close to P. caespitosa, but I cannot confirm the ID based on the given pictures.



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Persicaria prosumbu : 4 posts by 3 authors. Attachments (5)
I guess the plant is Pesicaria prosumbu. Please verify.
Shot at Mudkhu on 10 August 2016 at 5000 ft.

Difficult for me to guess with these pictures. P. longisetum and P. hydropiper are also closely allied to P. posumbu. If possible, plz check the perianth, seeds and cilia of the ochrea (which should be 6-8mm). I am providing a key (Adopted from Fl. China) for your convenience:
1. Perianth punctate…………………..P. hydropiper
1. Perianth not punctate………………………………2

2. Leaves ovate-lanceolate or ovate, apex caudate-acuminate, base broadly cuneate………………..P. posumbu
2. Leaves lanceolate or broadly lanceolate, apex acute or acuminate, base cuneate or rounded…..P. longiseta.
Hope this helps.


Persicaria caespitosa (Blume) Nakai  ??


I think it looks close to images at Persicaria posumbu (Buch.-Ham. ex D. Don) H. Gross


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ID of Polygonum sp from Assam KD 19.Jan 2015 : 3 posts by 2 authors. Attachments (7)
Attached images seem to be Polygonum sp. Please ID the plant.
Date :23.01.2015
Location: Assam
Family : Polygonaceae
Genus & species : Polygonum sp (?)
Habitat: Grows wild on open space
Habit : Herb


Looks like Persicaria pubescens (Blume) Hara
Family: Polygonaceae


I am having doubts of this being Persicaria pubescens (Blume) H. Hara, as per other images herein and as per GBIF specimens– onetwothree


May I request you to post high res. images to check the details.
I am leaning more towards Persicaria posumbu (Buch.-Ham. ex D. Don) H. Gross as per images and details herein.



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