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Polygonum douglasii
  • Knotweed

an annual member of the Polygonum genus in the family Polygonaceae.

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Niche
  • Unknown
    Unknown
    The ecosystem niches for this plant are unknown. Do you know them? Click the edit button to add them!
Functions
  • None
    None
    There are no functions defined for this plant. Do you know of some? Click the edit button to add them!
Light
  • Full sun
    Full sun
    The amount of sun exposure that a plant prefers in ideal conditions.
    Key
  • light shade
    Light shade
    The amount of shade a plant will tolerate without adverse health affects.
    Key
Water
  • Water Requirementsmoderate
    Moderate
    The amount of water a plant needs for healthy growth, relative to other plants.
    Key
Soil
  • acid,neutral,alkaline
    Unknown
    The PH range (acidity or alkilinity) of the growth medium ideal for healthy nutrient absorbtion.
    Key
  • Sandy to Clay
    The soil texture this plant prefers for optimal growth.
    Key
Cold & Heat
  • ?
    Unknown
    The USDA Hardiness scale assigns plants a number from 1 to 12 representing the minimum temperature a plant can survive.
    Key
    0< -53.9ºC< -65ºF
    1-51.1ºC-60ºF
    2-45.6ºC-50F
    3-40ºC-40ºF
    4-34.4ºC-30ºF
    5-28.9ºC-20ºF
    6-23.3ºC-10ºF
    7-17.8ºC0ºF
    8-12.2C10ºF
    9-6.7ºC20ºF
    10-1.1ºC30ºF
    114.4ºC40ºF
    12> 10ºC> 5ºF
  • ?
    Unknown
    The AHS Heat scale assigns plants a number from 1 to 12 representing the number of days per year a plant requires a temperature exceeding 30ºC (86ºF).
    Key
    11
    21 - 7
    38 - 14
    415 - 30
    531 - 45
    646 - 60
    761 - 90
    891 - 120
    9121 - 150
    10151 - 180
    11181 - 210
    12181 - 210
Polygonum douglasii has 0 edible uses listed

Uses

Toxic parts

Although no specific mention has been made for this species, there have been reports that some members of this genus can cause photosensitivity in susceptible people. Many species also contain oxalic acid (the distinctive lemony flavour of sorrel) - whilst not toxic this substance can bind up other minerals making them unavailable to the body and leading to mineral deficiency. Having said that, a number of common foods such as sorrel and rhubarb contain oxalic acid and the leaves of most members of this genus are nutritious and beneficial to eat in moderate quantities. Cooking the leaves will reduce their content of oxalic acid. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition[1].

Edible uses

Notes

Leaves - raw or cooked. Seed - dried then ground into a powder and mixed with cornmeal or other cereals for making bread etc[2][3][4][5][6]. The seed is rather small and fiddly to utilize, it is enclosed in a dry papery hull[7].

Leaves

Unknown use

Seed

Unknown use

Material uses

There are no material uses listed for Polygonum douglasii.

Medicinal uses(Warning!)

There are no medicinal uses listed for Polygonum douglasii.

Ecology

Ecosystem niche/layer

Ecological Functions

Nothing listed.

Forage

Nothing listed.

Shelter

Nothing listed.

Propagation

Seed - sow spring in a cold frame. Germination is usually free and easy. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer if they have reached sufficient size. If not, overwinter them in a cold frame and plant them out the following spring after the last expected frosts. Division in spring or autumn. Very easy, larger divisions can be planted out direct into their permanent positions. We have found that it is better to pot up the smaller divisions and grow them on in light shade in a cold frame until they are well established before planting them out in late spring or early summer.

Practical Plants is currently lacking information on propagation instructions of Polygonum douglasii. Help us fill in the blanks! Edit this page to add your knowledge.



Cultivation

We have very little information on this species and do not know if it is hardy in Britain, though judging by its native range it should succeed outdoors in most parts of the country. The following notes are based on the general needs of the genus.

Succeeds in an ordinary garden soil[8] but prefers a moisture retentive not too fertile soil in sun or part shade[9]. Repays generous treatment[8].

Plants seem to be immune to the predations of rabbits[10].

Crops

Problems, pests & diseases

Associations & Interactions

There are no interactions listed for Polygonum douglasii. Do you know of an interaction that should be listed here? edit this page to add it.

Polycultures & Guilds

There are no polycultures listed which include Polygonum douglasii.

Descendants

Cultivars

Varieties

None listed.

Subspecies

None listed.

Full Data

This table shows all the data stored for this plant.

Taxonomy
Binomial name
Polygonum douglasii
Genus
Polygonum
Family
Polygonaceae
Imported References
Edible uses
[2][3][4][5][6][7]
Medicinal uses
Material uses & Functions
Botanic
[11][12][13]
Propagation
Cultivation
Environment
Cultivation
Uses
Edible uses
None listed.
Material uses
None listed.
Medicinal uses
None listed.
Functions & Nature
Functions
Provides forage for
Provides shelter for
Environment
Hardiness Zone
?
Heat Zone
?
Water
moderate
Sun
full sun
Shade
light shade
Soil PH
acid, neutral, alkaline
Soil Texture
sandy, loamy, clay
Soil Water Retention
Environmental Tolerances
    Ecosystems
    Native Climate Zones
    None listed.
    Adapted Climate Zones
    None listed.
    Native Geographical Range
    None listed.
    Native Environment
    None listed.
    Ecosystem Niche
    None listed.
    Root Zone Tendancy
    None listed.
    Life
    Deciduous or Evergreen
    ?
    Herbaceous or Woody
    ?
    Life Cycle
    annual
    Growth Rate
    ?
    Mature Size
    0.3 x meters
    Fertility
    ?
    Pollinators
    Insects
    Flower Colour
    ?
    Flower Type
    hermaphrodite

    "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki. "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki. "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki.

    "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki. "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki.


    "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki.


    "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki., "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki., "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki. "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki., "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki., "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki.

    "image:Polygonumdouglasii.jpg|248px" cannot be used as a page name in this wiki.






    References

    1. ? Bown. D. Encyclopaedia of Herbs and their Uses. Dorling Kindersley, London. ISBN 0-7513-020-31 (1995-00-00)
    2. ? 2.02.1 Uphof. J. C. Th. Dictionary of Economic Plants. Weinheim (1959-00-00)
    3. ? 3.03.1 Usher. G. A Dictionary of Plants Used by Man. Constable ISBN 0094579202 (1974-00-00)
    4. ? 4.04.1 Tanaka. T. Tanaka's Cyclopaedia of Edible Plants of the World. Keigaku Publishing (1976-00-00)
    5. ? 5.05.1 Yanovsky. E. Food Plants of the N. American Indians. Publication no. 237. U.S. Depf of Agriculture. ()
    6. ? 6.06.1 Moerman. D. Native American Ethnobotany Timber Press. Oregon. ISBN 0-88192-453-9 (1998-00-00)
    7. ? 7.07.1 Coffey. T. The History and Folklore of North American Wild Flowers. Facts on File. ISBN 0-8160-2624-6 (1993-00-00)
    8. ? 8.08.1 F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press (1951-00-00)
    9. ? Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press ISBN 0-333-47494-5 (1992-00-00)
    10. ? Thomas. G. S. Perennial Garden Plants J. M. Dent & Sons, London. ISBN 0 460 86048 8 (1990-00-00)
    11. ? Fernald. M. L. Gray's Manual of Botany. American Book Co. (1950-00-00)
    12. ? Hitchcock. C. L. Vascular Plants of the Pacific Northwest. University of Washington Press (1955-00-00)
    13. ? Britton. N. L. Brown. A. An Illustrated Flora of the Northern United States and Canada Dover Publications. New York. ISBN 0-486-22642-5 (1970-00-00)

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    Facts about "Polygonum douglasii"RDF feed
    Article is incompleteYes +
    Article requires citationsNo +
    Article requires cleanupYes +
    Belongs to familyPolygonaceae +
    Belongs to genusPolygonum +
    Has binomial namePolygonum douglasii +
    Has common nameKnotweed +
    Has drought toleranceIntolerant +
    Has edible partLeaves + and Seed +
    Has edible useUnknown use +
    Has fertility typeInsects +
    Has flowers of typeHermaphrodite +
    Has imagePolygonumdouglasii.jpg +
    Has lifecycle typeAnnual +
    Has mature height0.3 +
    Has primary imagePolygonumdouglasii.jpg +
    Has search namepolygonum douglasii + and knotweed +
    Has shade toleranceLight shade +
    Has soil ph preferenceAcid +, Neutral + and Alkaline +
    Has soil texture preferenceSandy +, Loamy + and Clay +
    Has sun preferenceFull sun +
    Has taxonomic rankSpecies +
    Has taxonomy namePolygonum douglasii +
    Has water requirementsmoderate +
    Is taxonomy typeSpecies +
    PFAF cultivation notes migratedNo +
    PFAF edible use notes migratedNo +
    PFAF material use notes migratedYes +
    PFAF medicinal use notes migratedYes +
    PFAF propagation notes migratedNo +
    PFAF toxicity notes migratedNo +
    Tolerates nutritionally poor soilNo +
    Uses mature size measurement unitMeters +
    Has subobjectThis property is a special property in this wiki.Polygonum douglasii + and Polygonum douglasii +