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Quercus douglasii
  • Blue Oak

a perennial woody deciduous member of the Quercus genus in the family Fagaceae.

248px
Niche
  • Canopy
    Canopy
    There are no details available for this niche.
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
  • Loamy to Clay
    The soil texture this plant prefers for optimal growth.
    Key
Cold & Heat
  • 7
    Zone 7
    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
Quercus douglasii has 0 edible uses listed
Quercus douglasii has 0 material uses listed
Quercus douglasii has 0 medicinal uses listed

Uses

Edible uses

Notes

Seed - cooked[1]. The seed has been used as a staple food by some native North American Indian tribes[1]. Somewhat sweet[2][3][4][5]. A good size, to 25mm long and wide[6][7]. It can be dried, ground into a powder and used as a thickening in stews etc or mixed with cereals for making bread. The seed from some trees contains bitter tannins, these can be leached out by thoroughly washing the seed in running water though many minerals will also be lost. Either the whole seed can be used or the seed can be dried and ground it into a powder. It can take several days or even weeks to properly leach whole seeds, one method was to wrap them in a cloth bag and place them in a stream. Leaching the powder is quicker. A simple taste test can tell when the tannin has been leached. The traditional method of preparing the seed was to bury it in boggy ground overwinter. The germinating seed was dug up in the spring when it would have lost most of its astringency. The roasted seed is a coffee substitute.

Unknown part

Coffee

Seed

Unknown use

Material uses

A mulch of the leaves repels slugs, grubs etc, though fresh leaves should not be used as these can inhibit plant growth[8].

Oak galls are excrescences that are sometimes produced in great numbers on the tree and are caused by the activity of the larvae of different insects. The insects live inside these galls, obtaining their nutrient therein. When the insect pupates and leaves, the gall can be used as a rich source of tannin, that can also be used as a dyestuff[3]. The branches have been used to make rims for twined work baskets[1]. The acorn meal has been used to mend cracks in clay pots[1]. The seed cups are used as buttons[9].

Wood - hard, heavy, strong, brittle. It has a strong cross-grain and is difficult to split[10]. Of little commercial value, it is used mainly for fuel[6][10].

Unknown part

Adhesive
Basketry
Buttons
Fuel
Repellent
Tannin
Wood

Medicinal uses(Warning!)

Any galls produced on the tree are strongly astringent and can be used in the treatment of haemorrhages, chronic diarrhoea, dysentery etc[3]. A poultice of the ground galls and salt has been used in the treatment of burns, sores and cuts[1]. It has also been used as a wash for sore eyes[1]. The leaves have been chewed as a treatment for sore throats[1].

Unknown part

Astringent
Poultice
Skin

Ecology

Ecosystem niche/layer

Canopy

Ecological Functions

Nothing listed.

Forage

Nothing listed.

Shelter

Nothing listed.

Propagation

Seed - it quickly loses viability if it is allowed to dry out. It can be stored moist and cool overwinter but is best sown as soon as it is ripe in an outdoor seed bed, though it must be protected from mice, squirrels etc. Small quantities of seed can be sown in deep pots in a cold frame. Plants produce a deep taproot and need to be planted out into their permanent positions as soon as possible, in fact seed sown in situ will produce the best trees[11]. Trees should not be left in a nursery bed for more than 2 growing seasons without being moved or they will transplant very badly.

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



Cultivation

Prefers a good deep fertile loam which can be on the stiff side[12][11]. Young plants tolerate reasonable levels of side shade[7]. Tolerates moderate exposure, surviving well but being somewhat stunted[7].

Prefers warmer summers than are usually experienced in Britain, trees often grow poorly in this country and fail to properly ripen their wood resulting in frost damage overwinter[7]. A slow-growing but long-lived tree. Seed production is cyclic, a year of high yields being followed by 2 - 4 years of low production[10]. The tree flowers on new growth produced in spring, the seed ripening in its first year[7][10]. This species is notably resistant to honey fungus[13][7]. Hybridizes freely with other members of the genus[7].

Intolerant of root disturbance, trees should be planted in their permanent positions whilst young[11].

Crops

Problems, pests & diseases

Associations & Interactions

There are no interactions listed for Quercus 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 Quercus douglasii.

Descendants

Cultivars

Varieties

None listed.

Subspecies

None listed.

Full Data

This table shows all the data stored for this plant.

Taxonomy
Binomial name
Quercus douglasii
Genus
Quercus
Family
Fagaceae
Imported References
Edible uses
[1][2][3][4][5][6][7]
Medicinal uses
[3][1]
Material uses & Functions
[8][3][1][9][10][6]
Botanic
[11][6][7]
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
7
Heat Zone
?
Water
moderate
Sun
full sun
Shade
light shade
Soil PH
acid, neutral, alkaline
Soil Texture
loamy, clay
Soil Water Retention
Environmental Tolerances
  • Strong wind
Ecosystems
Native Climate Zones
None listed.
Adapted Climate Zones
None listed.
Native Geographical Range
None listed.
Native Environment
None listed.
Ecosystem Niche
Canopy
Root Zone Tendancy
None listed.
Life
Deciduous or Evergreen
deciduous
Herbaceous or Woody
woody
Life Cycle
perennial
Growth Rate
slow
Mature Size
12 x meters
Fertility
?
Pollinators
Wind
Flower Colour
?
Flower Type
monoecious

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

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


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

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

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

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






References

  1. ? 1.01.11.21.31.41.51.61.71.81.9 Moerman. D. Native American Ethnobotany Timber Press. Oregon. ISBN 0-88192-453-9 (1998-00-00)
  2. ? 2.02.1 Elias. T. and Dykeman. P. A Field Guide to N. American Edible Wild Plants. Van Nostrand Reinhold ISBN 0442222009 (1982-00-00)
  3. ? 3.03.13.23.33.43.5 Grieve. A Modern Herbal. Penguin ISBN 0-14-046-440-9 (1984-00-00)
  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. ? 6.06.16.26.36.4 Sargent. C. S. Manual of the Trees of N. America. Dover Publications Inc. New York. ISBN 0-486-20278-X (1965-00-00)
  7. ? 7.07.17.27.37.47.57.67.77.8 Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press ISBN 0-333-47494-5 (1992-00-00)
  8. ? 8.08.1 Riotte. L. Companion Planting for Successful Gardening. Garden Way, Vermont, USA. ISBN 0-88266-064-0 (1978-00-00)
  9. ? 9.09.1 Mabey. R. Food for Free. Collins ISBN 0-00-219060-5 (1974-00-00)
  10. ? 10.010.110.210.310.4 Elias. T. The Complete Trees of N. America. Field Guide and Natural History. Van Nostrand Reinhold Co. ISBN 0442238622 (1980-00-00)
  11. ? 11.011.111.211.3 Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray (1981-00-00)
  12. ? F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press (1951-00-00)
  13. ? RHS. The Garden. Volume 112. Royal Horticultural Society (1987-00-00)

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

Retrieved from "https://practicalplants.org/w/index.php?title=Quercus_douglasii&oldid=79956"
Facts about "Quercus douglasii"RDF feed
Article is incompleteYes +
Article requires citationsNo +
Article requires cleanupYes +
Belongs to familyFagaceae +
Belongs to genusQuercus +
Has common nameBlue Oak +
Has drought toleranceIntolerant +
Has edible partUnknown part + and Seeds +
Has edible useCoffee substitute + and Unknown use +
Has environmental toleranceHigh wind +
Has fertility typeWind +
Has flowers of typeMonoecious +
Has growth rateSlow +
Has hardiness zone7 +
Has imageLarge Blue Oak.jpg +
Has lifecycle typePerennial +
Has material partUnknown part +
Has material useAdhesive +, Basketry +, Buttons +, Fuel +, Repellent +, Tannin + and Wood +
Has mature height12 +
Has medicinal partUnknown part +
Has medicinal useAstringent +, Poultice + and Skin +
Has primary imageLarge Blue Oak.jpg +
Has search namequercus douglasii + and x +
Has shade toleranceLight shade +
Has soil ph preferenceAcid +, Neutral + and Alkaline +
Has soil teclayture preferenceClay +
Has soil teloamyture preferenceLoamy +
Has sun preferenceFull sun +
Has taxonomy nameQuercus douglasii +
Has water requirementsmoderate +
Inhabits ecosystem nicheCanopy +
Is deciduous or evergreenDeciduous +
Is herbaceous or woodyWoody +
Is taxonomy typeSpecies +
Tolerates nutritionally poor soilNo +
Tolerates windYes +
Uses mature size measurement unitMeters +