Spirodela polyrrhiza
(L.)Schleid.
Araceae
The Temperate Database is in the process of being updated, with new records being added and old ones being checked and brought up to date where necessary. This record has not yet been checked and updated.
Common Name: Great Duckweed
General Information
Spirodela polyrrhiza is a perennial plant that can grow up to 0.01 metres tall.
It is harvested from the wild for local use as a food and medicine
Known Hazards
None known
Botanical References
17- Title
- Flora of the British Isles.
- Publication
-
- Author
- Clapham, Tutin and Warburg.
- Publisher
- Cambridge University Press
- Year
- 1962
- ISBN
- -
- Description
- A very comprehensive flora, the standard reference book but it has no pictures.
,
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.
,
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
Europe, including Britain, south and east from Scandanavia to N. Africa and Asia. America, Australia
Habitat
Still water in ditches and ponds[
17- Title
- Flora of the British Isles.
- Publication
-
- Author
- Clapham, Tutin and Warburg.
- Publisher
- Cambridge University Press
- Year
- 1962
- ISBN
- -
- Description
- A very comprehensive flora, the standard reference book but it has no pictures.
]. Eutrophic, quiet waters, in temperate to tropical regions[
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 |  |
| Medicinal Rating |  |
| Habit | Perennial |
| Height | 0.01 m |
| Growth Rate | Fast |
| Cultivation Status | Wild |
Cultivation Details
Requires a sunny position in still water that is rich in nitrates and lime[
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.
].
A very small plant without differentiation into various parts such as leaf, stem etc (they are called Thalli), it is 8mm in diameter and often forming a mat on the water surface and perennating by means of buds (turions) that sink in autumn and rise to the surface in spring. The so-called rootcap (really only an apical swelling), has a higher specific gravity than any other part of the plant, righting capsized individuals[
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.
]. The plant rarely flowers, spreading mainly by vegetative means[
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.
].
Edible Uses
The plant is sometimes used as a food[
177- Title
- Plants for Human Consumption.
- Publication
-
- Author
- Kunkel. G.
- Publisher
- Koeltz Scientific Books
- Year
- 1984
- ISBN
- 3874292169
- Description
- An excellent book for the dedicated. A comprehensive listing of Latin names with a brief list of edible parts.
,
183- Title
- Cornucopia - A Source Book of Edible Plants.
- Publication
-
- Author
- Facciola. S.
- Publisher
- Kampong Publications
- Year
- 1990
- ISBN
- 0-9628087-0-9
- Description
- Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.
]. No more details are given.
Medicinal
The whole plant is antipruritic, antipyretic, cardiotonic, carminative, diaphoretic, diuretic[
147- Title
- A Barefoot Doctors Manual.
- Publication
-
- Author
- ?
- Publisher
- Running Press; Philadelphica.
- Year
- 1977
- ISBN
- 0-914294-92-X
- Description
- A very readable herbal from China, combining some modern methods with traditional chinese methods.
,
176- Title
- Handbook of Chinese Herbs and Formulas.
- Publication
-
- Author
- Yeung. Him-Che.
- Publisher
- Institute of Chinese Medicine, Los Angeles
- Year
- 1985
- ISBN
- -
- Description
- An excellent Chinese herbal giving information on over 500 species. Rather technical and probably best suited to the more accomplished user of herbs.
,
218- Title
- Medicinal Plants of China
- Publication
-
- Author
- Duke. J. A. and Ayensu. E. S.
- Publisher
- Reference Publications, Inc.
- Year
- 1985
- ISBN
- 0-917256-20-4
- Description
- Details of over 1,200 medicinal plants of China and brief details of their uses. Often includes an analysis, or at least a list of constituents. Heavy going if you are not into the subject.
]. It stimulates the appearance of measles rash[
147- Title
- A Barefoot Doctors Manual.
- Publication
-
- Author
- ?
- Publisher
- Running Press; Philadelphica.
- Year
- 1977
- ISBN
- 0-914294-92-X
- Description
- A very readable herbal from China, combining some modern methods with traditional chinese methods.
,
176- Title
- Handbook of Chinese Herbs and Formulas.
- Publication
-
- Author
- Yeung. Him-Che.
- Publisher
- Institute of Chinese Medicine, Los Angeles
- Year
- 1985
- ISBN
- -
- Description
- An excellent Chinese herbal giving information on over 500 species. Rather technical and probably best suited to the more accomplished user of herbs.
]. It is used in the treatment of colds, measles, oedema and difficulty in urination[
176- Title
- Handbook of Chinese Herbs and Formulas.
- Publication
-
- Author
- Yeung. Him-Che.
- Publisher
- Institute of Chinese Medicine, Los Angeles
- Year
- 1985
- ISBN
- -
- Description
- An excellent Chinese herbal giving information on over 500 species. Rather technical and probably best suited to the more accomplished user of herbs.
].
Other Uses
None known
Propagation
The plant divides freely in the growing season and does not need help.
If you have any useful information about this plant, please leave a comment. Comments have to be approved before they are shown here.
Useful Temperate Plants Database 2016 by
Ken Fern,
web interface by
Ajna Fern
with help from
Richard Morris.
