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Useful Temperate Plants

Polygonum douglasii

Greene

Polygonaceae

+ Synonyms

Polygonum buxiforme montanum (Brenckle) R.J.Davis

Polygonum commixtum Greene

Polygonum howellii Greene

Polygonum montanum (Small) Greene

Polygonum tenue commune Engelm.

Polygonum tenue latifolium Engelm.

Polygonum vagans Greene

Common Name: Douglas' Knotweed

No Image.

General Information

Polygonum douglasii is an erect, unbranched or branched, annual plant that can grow around 5 - 80cm tall[
270
Title
Flora of N. America
Publication
 
Author
 
Website
http://flora.huh.harvard.edu/fna/
Publisher
 
Year
0
ISBN
 
Description
An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.
].
The plant is harvested from the wild for local use as a food.

Known Hazards

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[
238
Title
Encyclopaedia of Herbs and their Uses.
Publication
 
Author
Bown. D.
Publisher
Dorling Kindersley, London.
Year
1995
ISBN
0-7513-020-31
Description
A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.
].

Botanical References

43
Title
Gray's Manual of Botany.Eighth Edition
Publication
 
Author
Fernald. M. L.
Publisher
American Book Co.; New York
Year
1950
ISBN
0442222505
Description
A bit dated but a good and concise flora of the eastern part of N. America.
,
60
Title
Vascular Plants of the Pacific Northwest.
Publication
 
Author
Hitchcock. C. L.
Publisher
University of Washington Press
Year
1955
ISBN
-
Description
A standard flora for Western N. America with lots of information on habitat etc. Five large volumes, it is not for the casual reader.
,
270
Title
Flora of N. America
Publication
 
Author
 
Website
http://flora.huh.harvard.edu/fna/
Publisher
 
Year
0
ISBN
 
Description
An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.

Range

N. America - Yukon and British Columbia to Quebec, south to California and NW Mexico, New Mexico, Iowa, Michigan and New Hampshire

Habitat

Dry, often disturbed places, rock outcrops, sandy ground; at elevations from 300 - 3,000 metres[
270
Title
Flora of N. America
Publication
 
Author
 
Website
http://flora.huh.harvard.edu/fna/
Publisher
 
Year
0
ISBN
 
Description
An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.
].

Properties

Edibility Rating *  *
HabitAnnual
Height0.30 m
PollinatorsInsects
Cultivation StatusWild

Cultivation Details


Species in this genus generally succeed in an ordinary garden soil, whilst preferring a moisture retentive not too fertile soil in sun or part shade[
200
Title
The New RHS Dictionary of Gardening. 1992.
Publication
 
Author
Huxley. A.
Publisher
MacMillan Press
Year
1992
ISBN
0-333-47494-5
Description
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
]. They generally rpays generous treatment[
1
Title
RHS Dictionary of Plants plus Supplement. 1956
Publication
 
Author
F. Chittendon.
Publisher
Oxford University Press
Year
1951
ISBN
-
Description
Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [200]).
].
Most plants in this genus seem to be immune to the predations of rabbits[
233
Title
Perennial Garden Plants
Publication
 
Author
Thomas. G. S.
Publisher
J. M. Dent & Sons, London.
Year
1990
ISBN
0 460 86048 8
Description
A concise guide to a wide range of perennials. Lots of cultivation guides, very little on plant uses.
].

Edible Uses

Leaves - raw or cooked.

Seed - dried then ground into a powder and mixed with cornmeal or other cereals for making bread etc[
46
Title
Dictionary of Economic Plants.
Publication
 
Author
Uphof. J. C. Th.
Publisher
Weinheim
Year
1959
ISBN
-
Description
An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.
,
61
Title
A Dictionary of Plants Used by Man.
Publication
 
Author
Usher. G.
Publisher
Constable
Year
1974
ISBN
0094579202
Description
Forget the sexist title, this is one of the best books on the subject. Lists a very extensive range of useful plants from around the world with very brief details of the uses. Not for the casual reader.
,
105
Title
Tanaka's Cyclopedia of Edible Plants of the World.
Publication
 
Author
Tanaka. T. & Nakao S.
Publisher
Keigaku Publishing; Tokyo
Year
1976
ISBN
-
Description
The most comprehensive list of edible plants I've come across. Only the briefest entry for each species, though, and some of the entries are more than a little dubious. Not for the casual reader.
,
161
Title
Food Plants of the N. American Indians. Publication no. 237.
Publication
 
Author
Yanovsky. E.
Publisher
U.S. Depf of Agriculture.
Year
 
ISBN
-
Description
A comprehensive but very terse guide. Not for the casual reader.
,
257
Title
Native American Ethnobotany
Publication
 
Author
Moerman. D.
Publisher
Timber Press. Oregon.
Year
1998
ISBN
0-88192-453-9
Description
Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.
]. The seed is rather small and fiddly to utilize, it is enclosed in a dry papery hull[
207
Title
The History and Folklore of North American Wild Flowers.
Publication
 
Author
Coffey. T.
Publisher
Facts on File.
Year
1993
ISBN
0-8160-2624-6
Description
A nice read, lots of information on plant uses.
].

Medicinal

None known

Other Uses

None known

Propagation

Seed - sow spring in situ
Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2022-10-04. <temperate.theferns.info/plant/Polygonum+douglasii>

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