Click on the language to view common names.
Common Names in English:
Douglas Knotweed, Douglas´s Knotweed, Douglas' Knotweed, Douglas's Knotweed
Common Names in French:
Renouée De Douglas
, or small trees
, sometimes monoecious or dioecious. Stems erect
, or scandent
, often with swollen nodes, striate
, or prickly. Leaves simple
, alternate, rarely opposite or whorled
; stipules often united
to a sheath
(ocrea) . Inflorescence terminal
, racemose, paniculate
, or capitate. Pedicel occasionally articulate
. Flowers small, actinomorphic
, rarely unisexual
. Perianth 3-6-merous, in 1 or 2 series, herbaceous, often enlarged in fruit or inner tepals enlarged, with wings
, or spines. Stamens usually (3-) 6-9, rarely more; filaments
or united at base
2-loculed, opening lengthwise; disk annular
) . Ovary superior, 1-loculed; styles 2 or 3, rarely 4, free or connate
at lower part. Fruit a trigonous
, or biconcave
achene; seed with straight or curved
embryo and copious
About 50 genera and 1120 species: worldwide, but primarily N temperate with a few species in tropical regions ; 13 genera (two endemic) and 238 species (65 endemic) in China.
, or subshrubs
in P. striatulum), homophyllous
, sometimes heterocarpic; roots
or woody. Stems prostrate
or sometimes papillous-scabridulous. Leaves cauline, alternate (opposite in P. humifusum), petiolate
or sessile; ocrea with distal part persistent
, often hyaline
, white or silvery, 2-lobed, chartaceous
, glabrous, disintegrating into fibers, or disintegrating completely; petiole
articulated with ocrea or not; blade
, lanceolate, elliptic
, or subround, margins
entire. Inflorescences axillary
or axillary and terminal
, spikelike, or flowers solitary; peduncle absent. Pedicels present or absent. Flowers bisexual
, 1-7(-10) per ocreate
fascicle, base not stipelike; perianth nonaccrescent, white or greenish white to pink, campanulate
, glabrous; tepals 5, connate
3-70% of their length
or, rarely, dimorphic
, the inner usually flat, the outer flat or sometimes keeled
distally, sometimes of different length than the inner; stamens 3-8 (some may be reduced to staminodes) ; filaments
to perianth tube, glabrous; anthers
whitish yellow, pink to purple or orange-pink, elliptic to oblong
; styles (2-) 3, mostly spreading
, distinct or connate proximally; stigmas 2-3, capitate. Achenes included
or exserted, yellow-green, brown, or black, unwinged, (2-) 3-gonous, glabrous. Seeds: embryo curved
. x = 10.
Species ca. 65: nearly worldwide.
Two sections of Polygonum are recognized here. Section Polygonum is nearly cosmopolitan and best represented in north-temperate regions; sect. Duravia comprises species restricted to North America. K . Haraldson (1978) recognized both sections based on differences in stem morphology, petiole structure, and pollen morphology. J. C. Hickman (1984) described sect. Monticola and included in it species of sect. Duravia occurring mostly in montane habitats , with leaves articulated to the ocreae, one-veined, and not mucronate , proximal leaves lanceolate to round , and styles connate at their bases and neither hardened nor persistent. L.-P. Ronse Decraene and J. R. Akeroyd (1988) and L.-P. Ronse Decraene et al. (2000) included sect. Duravia in sect. Polygonum based on floral and fruit characters.
Similarities in floral structure, fruit anatomy, and pollen morphology have been noted between Polygonella with Polygonum (L.-P. Ronse Decraene et al. 2000). Based on evidence from comparative morphological studies, Ronse Decraene et al. (2004) included Polygonella in sect. Duravia of Polygonum.
Four introduced taxa of sect. Polygonum that were collected in the flora area at the end of the nineteenth century and beginning of the twentieth century appear not to have persisted here and are not included in the keys . Polygonum arenarium Waldstein & Kitaibel and P. bellardii Allioni were reported by B . L. Robinson (1902) from Rhode Island and Massachusetts, respectively. The former resembles P. patulum but has open flowers. Polygonum bellardii is discussed below under P. ramosissimum. Polygonum polycnemoides Jaubert & Spach and P. humifusum C. Merck ex K. Koch subsp. humifusum were reported by J. F. Brenckle (1941). The former was collected in New York City in 1894 and in Idaho in 1940. It differs from all other Polygonum species in having a tube 55-70% of the perianth length. Polygonum humifusum subsp. humifusum is discussed below under P. humifusum subsp. caurianum.
Species Polygonum douglasii
Herbs. Stems erect
, green, simple
or branched, not wiry, 5-80
or sparsely papillose-scabridulous. Leaves uniformly
distributed, articulated to ocreae, basal leaves
leaves abruptly reduced to bracts; ocrea 6-12 mm, glabrous or minutely
, distal part hyaline
0.1-2 mm; blade
1-veined, not pleated
narrow-oblong, or oblanceolate
, 15-55 × 2-8(-12) mm, margins
or papillose-denticulate; apex acute to mucronate
, spikelike, elongate
cymes widely spaced along branches, 2-4-flowered. Pedicels
mostly exserted from ocreae, reflexed
, 2-6 mm.
perianth 3-4.5 mm; tube
20-28% of perianth length; tepals overlapping,
green to tannish with white or pink margins, petaloid
, apex rounded
usually branched, rarely unbranched;
stamens 8. Achenes enclosed in perianth, black, elliptic
oblong to ovate
, 3-4(-4.5) mm, faces
, shiny or dull
or minutely striate-tubercled. [source]
Five taxa that have been included in Polygonum douglasii (E. Murray 1982; J. C. Hickman 1984; J. T. Kartesz and K . N. Gandhi 1990) are treated here as distinct species: P. austiniae, P. majus, P. nuttallii, P. sawatchense, and P. spergulariiforme. Hickman noted extensive intergradation and numerous intermediate specimens among those sympatric elements , but qualitative or quantitative characters allow reliable discrimination in most cases (M. Costea and F. J. Tardif 2005), and species are here circumscribed similar to C. L. Hitchcock (1964). [source]
Greene described var. latifolium as having leaf blades and achenes broader than those of var. douglasii. C. L. Hitchcock (1964) recognized the former, but the characters used to distinguish it appear to vary continuously, and reliable separation is not possible. [source]
Flowers: Bloom Period: June, July, August, September, October.
Dry, often disturbed places, rock outcrops, sandy ground ; 300-3000 m .
Typically found at an altitude of 0 to 3,632 meters (0 to 11,916 feet).
- Whittaker & Margulis,1978
- Haeckel, 1866
- Cavalier-Smith, 1981
- Sinnott, 1935 ex Cavalier-Smith, 1998
- Vascular Plants
- Kenrick & Crane, 1997
- Brongniart, 1843
- Takhtajan, 1967
- Takhtajan Ex Reveal, 1992
- Perleb, 1826
- A.L. de Jussieu, 1789, nom. cons.
- knotweed, renouées
- Subfamily: Polygonoideae ()
- Family: Polygonaceae () - A.L. de Jussieu, 1789, nom. cons. - knotweed, renouées
- Order: Caryophyllales () - Perleb, 1826
- Superorder: Polygonanae () - Takhtajan Ex Reveal, 1992
- Subclass: Caryophyllidae () - Takhtajan, 1967
- Class: Spermatopsida () - Brongniart, 1843
- Infraphylum: Radiatopses () - Kenrick & Crane, 1997
- Subphylum: Euphyllophytina ()
- Phylum: Tracheophyta () - Sinnott, 1935 ex Cavalier-Smith, 1998 - Vascular Plants
- Subkingdom: Viridaeplantae () - Cavalier-Smith, 1981
- Kingdom: Plantae () - Haeckel, 1866 - Plants
P. emaciatum A. Nelson • P. montanum (Small) Greene • P. tenue Michaux Var. commune Engelmann • P. tenue var. latifolium Engelmann • Polygonum douglasii var. latifolium (Engelmann) Greene
Status: Accepted Name
Last scrutiny: 15-Mar-2000
Members of the genus Polygonum
ZipcodeZoo has pages for 134 species, subspecies, varieties, forms, and cultivars in this genus. Here are just 100 of them:
P. achoreum (Leathery Knotweed) · P. acuminatum (Tapertip Smartweed) · P. affine (Himalayan Fleece Flower) · P. alpinum (Alaska Wild Rhubarb) · P. amphibium (Longroot Smartweed) · P. amphibium var. emersum (Longroot Smartweed) · P. amphibium var. stipulaceum (Swamp Smartweed) · P. arenarium (European Knotweed) · P. arenastrum (Common Knotweed) · P. argyrocoleon (Persian Knotweed) · P. arifolium (Halberdleaf Tearthumb) · P. aubertii (Chinese Fleecevine) · P. aubertii 'Lemon Lace' (Silverlace Vine) · P. aviculare (Birdgrass) · P. aviculare angustissimum (Prostrate Knotweed) · P. aviculare aviculare (Prostrate Knotweed) · P. aviculare neglectum (Prostrate Knotweed) · P. baldschuanicum (Bukhara Fleeceflower) · P. bellardii (Narrowleaf Knotweed) · P. bidwelliae (Bidwell's Knotweed) · P. bistorta (Meadow Bistort) · P. bistorta carneum (Meadow Bistort) · P. bistorta var. bistorta (Meadow Bistort) · P. bistorta var. plumosum (Meadow Bistort) · P. bistorta 'Superbum' (European Bistort) · P. bistortoides (American Bistort) · P. bohemicum (Bohemian Knotweed) · P. bolanderi (Bolander's Knotweed) · P. boreale (Northern Knotweed) · P. bungeanum (Bunge's Smartweed) · P. buxiforme (Box Knotweed) · P. caespitosum (Bristled Knotweed) · P. caespitosum var. caespitosum (Oriental Ladysthumb) · P. caespitosum var. longisetum (Oriental Ladysthumb) · P. californicum (California Knotweed) · P. campanulatum (Bellflower Smartweed) · P. capathifolium (Grey Moray) · P. capitatum (Pink Knotweed) · P. careyi (Carey's Smartweed) · P. cascadense (Cascade Knotweed) · P. caurianum (Alaska Knotweed) · P. chinense (Chinese Knotweed) · P. cilinode (Fringed Black Bindweed) · P. convolvulus (Black Bindweed) · P. convolvulus var. convolvulus (Knot Grass) · P. convolvulus var. subulatum (Wild Buckwheat) · P. cuspidatum 'Crimson Beauty' (False Bamboo) · P. cuspidatum 'Devon Cream' (False Bamboo) · P. cuspidatum 'Freckles' (Speckled Mexican Bamboo) · P. cuspidatum 'Variegata' (Speckled Mexican Bamboo) · P. davisiae (Davis' Knotweed) · P. densiflorum (Denseflower Knotweed) · P. douglasii (Douglas Knotweed) · P. douglasii nuttalii (Douglas´s Knotweed) · P. douglasii var. douglasii (Douglas´s Knotweed) · P. douglasii subsp. austiniae (Austin's Knotweed) · P. douglasii subsp. engelmannii (Engelmann's Knotweed) · P. douglasii subsp. johnstonii (Johnston's Knotweed) · P. douglasii subsp. majus (Large Knotweed) · P. douglasii subsp. nuttallii (Nuttall's Knotweed) · P. douglasii subsp. spergulariiforme (Scatter Knotweed) · P. emersum (Longroot Smartweed) · P. equisetiforme (Horsetail Knotgrass) · P. erectum (Devil's Shoestring) · P. fowleri (Fowler's Knotweed) · P. franktonii (Nova Scotia Knotweed) · P. glaucum (Seaside Knotweed) · P. herniarioides (Knotweed) · P. heterosepalum (Oddsepal Knotweed) · P. hickmanii (Hickman's Knotweed) · P. hirsutum (Hairy Smartweed) · P. hydropiper (Annual Smartweed) · P. hydropiperoides (Mild Water-Pepper) · P. islandicum (Island Purslane) · P. lacerum (Fringed Knotweed) · P. lapathifolium (Curltop Ladysthumb) · P. lapathifolium var. lapathifolium (Curltop Ladysthumb) · P. leptocarpum (Narrow-Point Knotweed) · P. marinense (Marin Knotweed) · P. meisnerianum (Branched Tearthumb) · P. meisnerianum var. beyrichianum (Branched Tearthumb) · P. minimum (Broadleaf Knotweed) · P. mite (Tasteless Water Pepper) · P. multiflorum (Fo-Ti) · P. nepalense (Nepalese Smartweed) · P. odoratum (Vietnamese Coriander) · P. orientale (Kiss Me Over the Garden Gate) · P. orientale 'Shiro-Gane Nishiki' (Variegated Kiss Me Over The Garden Gate) · P. oxyspermum (Sharpfruit Knotweed) · P. oxyspermum raii (Sharpfruit Knotweed) · P. paronychia (Beach Knotweed) · P. paronychioides (Knotweed) · P. parryi (Parry's Knotweed) · P. patulum (Bellard's Smartweed) · P. pensylvanicum (Pennsylvania Knotweed) · P. perfoliatum (Asiatic Tear Thumb) · P. persicaria (Lady's Thumb) · P. persicaria persicaria (Lady's-Thumb) · P. phytolaccifolium (Mountain Lice) · P. polycnemoides (Manyleg Knotweed)
- Search for Pictures: images.google.com
- Search for Scholarly Articles: Google Scholar
- Search using Scientific Name and Vernacular Names: All the Web | AltaVista Canada | AltaVista | Excite | Google | HotBot | Lycos
- Search using Specialized Databases: GenBank | Medline | Scirus | CISTI/CAL | Agricola Periodicals | Agricola Books
- ... A monograph of the North American species of the genus Polygonum. By John Kunkel Small. (Lancaster, Pa., The New era print)1895. url p. 211.
- ... Flora of Glacier National Park, Montana, by Paul C. Standley. Washington, Govt. Print. Off., 1921. url p. 328.
- A flora of California, by Willis Linn Jepson. San Francisco, Calif., Cunningham, Curtis & Welch, 1909- url p. 382, p. 382.
- A preliminary classification of the plant communities of northeastern Montana / Robert L. DeVelice [et al.]. Helena, MT: Montana Natural Heritage Program, c1991. url , , , , , .
- A vegetation index of biotic integrity for small-order streams in southwest Montana and a floristic quality assessment for western Montana wetlands / [Helena, Mont.: Montana Natural Heritage Program, c2005]. url , .
- Annual report of the Regents / Albany: J.B. Lyon, State Printer, 1890-1903. url p. 161, p. 199.
- Botanical and vegetation survey of Carter County, Montana, Bureau of Land Management-administered lands / prepared by Jim Vanderhorst, Stephen V. Cooper, and Bonnie L. Heidel; prepared for United States Department of the Interior, Bureau of Land Management. Helena, MT: Montana Natural Heritage Program,  url , p. 33.
- Brigham Young University science bulletin. 16 1972 Provo, Utah: Brigham Young University, [1955-1976] url p. 18, p. 6.
- Budd's flora of the Canadian Prairie Provinces / [Ottawa]: Research Branch, Agriculture Canada, 1987. url p. 317.
- Bulletin / U.S. Department of Agriculture, Bureau of Plant Industry. Washington: G.P.O., 1901-1913. url p. 21, p. 22, p. 49.
- Bulletin from the laboratories of natural history of the State University of Iowa. Iowa City, Iowa: The University, 1888-. url , p. 226, p. 228.
- Bulletin of the Torrey Botanical Club. 19 1892 New York: Torrey Botanical Club, 1870-1996 url p. 365.
- Bulletin of the U.S. Department of Agriculture. [Washington, D.C.?]: Supt. of Docs., G.P.O., 1913-1923. url , p. 44, p. 47.
- Bulletin. Washington, Govt. Print. Off.1889-1913. url p. 10.
- Carnegie Institution of Washington publication. Washington, Carnegie Institution of Washington, 1902- url p. 187, p. 36, p. 42.
- Contributions from the United States National Herbarium 5 1897-1901 Washington, D.C.: Smithsonian Institution Press, 1890- url p. 107, p. 145, p. 161, p. 162, p. 194, p. 195, p. 229, p. 249, p. 280, p. 327, p. 328, p. 521, p. 95.
- Distribution of vascular plant species of special concern and limited distribution in the Pryor Mountain Desert; Carbon County, Montana / prepared by Peter Lesica and Peter L. Achuff; prepared for USDI Bureau of Land Management, Montana State Office. Helena, Mont.: Montana Natural Heritage Program,  url .
- Entomological news, and proceedings of the Entomological Section of the Academy of Natural Sciences of Philadelphia. Philadelphia[Entomological Rooms of the Academy of Natural Sciences] url p. 312.
- Entomological news. [Philadelphia]American Entomological Society, 1925- url p. 241.
- Flora of New Mexico / by E.O. Wooton and Paul C. Standley. Washington: G.P.O., 1915. url p. 195.
- Flora of New Mexico. By E.O. Wooton and Paul C. Standley. WashingtonGovt. Print. Off.1915 url p. 195.
- Flora of southeastern Washington and adjacent Idaho / by Charles V. Piper and R. Kent Beattie. Lancaster, Pa.: New Era, 1914. url p. 86.
- Flora of the Black Hills of South Dakota. By P.A. Rydberg. Washington, Govt. Print. Off., 1896. url p. 521.
- Flora of the District of Columbia and vicinity. By A.S. Hitchcock and Paul C. Standley, with the assistance of the botanists of Washington. WashingtonGovt. print. off.1919 url p. 145.
- Flora of the northwest coast, including the area west of the summit of the Cascade Mountains, from the forty-ninth parallel south to the Calapooia Mountains on the south border of Lane County, Oregon. Lancaster, Pa., Press of the New Era Printing Company, 1915. url .
- Flora of the northwest coast: including the area west of the summit of the Cascade Mountains, from the forty-ninth parallel south to the Calapooia Mountains on the south border of Lane County, Oregon / by Charles V. Piper and R. Kent Beattie. Lancaster, Pa.: Press of the New era printing company, 1915. url p. 130.
- Flora of the southeastern Washington and adjacent Idaho, Lancaster, Pa., Press of the New Era Printing Company, 1914. url .
- Flora of the state of Washington / by Charles V. Piper. Washington: G.P.O., 1906 url p. 229.
- Flora of the state of Washington. By Charles V. Piper. Washington, Govt. Print. Off., 1906. url p. 229.
- Great Basin naturalist memoirs. 1987 [Provo, Utah]Brigham Young University, 1976-1992. url p. 489.
- Journal of agricultural research. Washington, U.S. Govt. Printing Office, 1913-1949.. url p. 124.
- Miscellaneous publication - University of Kansas, Museum of Natural History. 1969 Lawrence: University of Kansas, 1946-1996. url p. 52.
- Mount Rainier: a record of exploration / edited by Edmond S. Meany. New York: Macmillan, 1916. url p. 278.
- National list of scientific plant names. [Washington, D.C.]: U.S. Dept. of Agriculture, Soil Conservation Service, 1982- url p. 327.
- Notes on western range forbs: Equisetaceae through Fumariaceae / by William A. Dayton. Washington, D.C.: Forest Service, U.S. Dept. of Agriculture, 1960. url p. 77.
- Pamphlets on forestry in Nebraska. [1900?- url p. 15.
- Phytogeography of Nebraska. 1. General survey by Roscoe Pound and Frederic E. Clements. Lincoln, Neb.Published by the Seminar1900 url p. 85.
- Phytologia. Bronx Park, New York, H.A. Gleason and H.N. Moldenke, url p. 299, p. 424, p. 93.
- Plant community classification for vegetation on BLM lands, Pryor Mountains, Carbon County, Montana / Robert L. DeVelice & Peter Lesica; for USDI Bureau of Land Management, State Office. Helena, Mt.: Montana Natural Heritage Program, c1993. url p. 51.
- Proceedings of the California Academy of Sciences. San Francisco, Calif.: The Academy, 1897-1904. url .
- Rare plant inventory and plant community descriptions of the Sweet Grass Hills, Proposed Area of Critical Environmental Concern (PACEC), Toole and Liberty Counties, Montana / prepared for United States Department of Interior, Bureau of Land Management; prepared by Western Technology and Engineering, Inc. in cooperation with Montana Natural Heritage Program. Helena, MT: Western Technology and Engineering, Inc.,  url .
- Sensitive plant species survey, Ashland District, Custer National Forest, Powder River and Rosebud Counties, Montana / by Bonnie L. Heidel and Hollis Marriott; for Custer National Forest. Helena, MT: Montana Natural Heritage Program,  url .
- Sensitive plant survey of the Sage Creek Area, Beaverhead County, Montana, Dillon Resource Area, Bureau of Land Management / prepared by Peter Lesica and Jim Vanderhorst; prepared for USDI Bureau of Land Management, Butte District. Helena, Mt.: Montana Natural Heritage Program,  url p. 40.
- Sensitive plant survey of the Tendoy Mountains, in the Beaverhead National Forest, Beaverhead County, Montana / prepared by Jim Vanderhorst; prepared for United States Forest Service, Beaverhead National Forest. Helena, Mt.: Montana Natural Heritage Program,  url p. 11, p. 44.
- Sensitive plant surveys in the Big Belt and Elkhorn Mountains, U.S.D.A. Forest Service, Region 1, Helena National Forest, Montana / prepared by Jackie M. Poole and Bonnie L. Heidel; prepared for Helena National Forest. Helena, Mont.: Montana Natural Heritage Program,  url , , , , , , , .
- Sensitive plant surveys in the Gallatin National Forest, Montana / prepared by Jim Vanderhorst; prepared for U.S. Forest Service, Gallatin National Forest. Helena, MT: Montana Natural Heritage Program, . url p. 77.
- Sensitive, threatened, and endangered vascular plants of Montana / Peter Lesica, J. Stephen Shelly. Helena, Mont.: Montana Natural Heritage Program, Montana State Library, 1991. url p. 87.
- Survey for Psoralea hypogaea in the Great Falls Resource Area, Lewistown District, Bureau of Land Management, Montana / Helena, Mont.: Montana Natural Heritage Program, c1994. url , p. 12.
- Survey for Quercus macrocarpa in the Powder River Resource Area, Miles City District, Bureau of Land Management, Montana / prepared for Bureau of Land Management, Miles City District Office; prepared by Bonnie L. Heidel. Helena, Mont.: Montana Natural Heritage Program, . url p. 15, p. 8.
- Survey for sensitive plant species on BLM lands in the vicinity of Lemhi Pass, Beaverhead County / prepared by Jim Vanderhorst; prepared for Bureau of Land Management, Butte District. Helena, MT: Montana Natural Heritage Program, . url .
- Syllogeus. Ottawa, National Museum of Natural Sciences, 1972-1995. url p. 14, p. 14, p. 15, p. 49, p. 51, p. 72, p. 76.
- The Canadian entomologist. Ottawa [etc.]Entomological Society of Canada [etc.] url p. 83.
- The Canadian field-naturalist. Ottawa, Ottawa Field-Naturalists' Club. url p. 169, p. 233, p. 335, p. 339, p. 340, p. 443, p. 52.
- The Great Basin naturalist. 41 1981 Provo, Utah: M.L. Bean Life Science Museum, Brigham Young University, 1939-1999. url p. 102, p. 114, p. 149, p. 157, p. 169, p. 229, p. 292, p. 552, p. 56, p. 575, p. 637, p. 97.
- The Mountaineer. Seattle, The Mountaineers, 1907-1921. url p. 112.
- The Plant world. Baltimore [etc.]Plant World Association [etc.] url p. 189, p. 282.
- The vegetation of a desert mountain range as conditioned by climatic factors, Washington, D. C., Carnegie Institution of Washington, 1915. url , .
- University studies of the University of Nebraska. Lincoln. url p. 335.
- Vascular plant and sensitive plant species inventory for the highland mountains, Deerlodge National Forest; prepared for Deerlodge National Forest / prepared by Peter Lesica. Helena, Mont.: Montana Natural Heritage Program,  url p. 24, p. 45.
- Vegetation and flora of the Line Creek Plateau area, Carbon County, Montana / prepared by Peter Lesica and the Montana Natural Heritage Program; prepared for USDA Forest Service, Intermountain Research Station. Helena, MT: Montana Natural Heritage Program,  url p. 28.
- Woodhawk botanical survey, Fergus County, Montana, Lewistown District of the Bureau of Land Management / Helena, Mont.: Montana Natural Heritage Program, c1997. url p. 24.
- Li Anjen, Kao Tsoching, Mao Zumei & Liu Yulan. 1998. Polygonaceae. In: Li Anjen, ed., Fl. Reipubl. Popularis Sin. 25(1): 1209.
- Jones, D. M. and T. R. Mertens. 1970. A taxonomic study of genus Polygonum employing chromatographic methods. Proc. Indiana Acad. Sci. 80: 422-430.
- Brands, S.J. (comp.) 1989-present. The Taxonomicon. Universal Taxonomic Services, Zwaag, The Netherlands. Accessed January 30, 2012.
Accessed through GBIF Data Portal February 02, 2008:
- Berkeley Natural History Museums, University and Jepson Herbaria DiGIR provider
- Bundesamt für Naturschutz / Zentralstelle für Phytodiversität Deutschland, Bundesamt fuer Naturschutz / Zentralstelle fuer Phytodiversitaet Deutschland
- Canadian Museum of Nature, Canadian Museum of Nature Herbarium
- Missouri Botanical Garden, Missouri Botanical Garden
- National Herbarium of New South Wales, Plants of Papua New Guinea
- Oregon State University, Vascular Plant Collection
- School of Life Sciences, Arizona State University, Arizona State University Vascular Plant Herbarium
- School of Life Sciences, Arizona State University, The Deaver Herbarium, Northern Arizona University
- USDA PLANTS, USDA PLANTS Database
- University of Colorado Museum, Zoological specimens
- University of Washington Burke Museum, Vascular Plant Collection - University of Washington Herbarium
- Utah State University, USU-UTC Specimen Database
- Utah Valley State College
- , Utah Valley State College Herbarium
- Biodiversity Heritage Library NamebankID: 2647027
- Catalogue of Life Accepted Name Code: ITS-20891
- GRIN Nomen Number: 452226
- Integrated Taxonomic Information System (ITIS) Taxonomic Serial Number (TSN): 20891
- International Plant Names Index (IPNI) ID: 695669-1
- U.S.D.A. Plant Symbol: POCOM3 POS
- Zipcode Zoo Species Identifier: 57539
- Anjen Li, Bojian Bao, Alisa E. Grabovskaya-Borodina, Suk-pyo Hong, John McNeill, Sergei L. Mosyakin, Hideaki Ohba & Chong-wook Park "Polygonaceae". in Flora of China Vol. 5 Page 277. Published by Science Press (Beijing) and Missouri Botanical Garden Press. Online at EFloras.org. [back]
- Mihai Costea, François J. Tardif, Harold R. Hinds "Polygonum". in Flora of North America Vol. 5. Oxford University Press. Online at EFloras.org. [back]
- "Polygonum douglasii". in Flora of North America Vol. 5. Oxford University Press. Online at EFloras.org. [back]
- Mean = 1,233.690 meters (4,047.539 feet), Standard Deviation = 629.250 based on 1,035 observations. Altitude information for each observation from British Oceanographic Data Centre. [back]