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Rhus diversiloba
  • Western Poison Oak

a perennial woody deciduous member of the Rhus genus in the family Anacardiaceae.

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
  • no shade
    No 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
    Acid to Alkaline
    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
  • 5
    Zone 5
    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
Rhus diversiloba has 0 material uses listed
Rhus diversiloba has 0 medicinal uses listed

Uses

Toxic parts

All parts of the plant contain resinous phenolic compounds known as urushiols. Direct contacr with the plant, exposure to smoke or fumes from a burning plant or even contact with pets or animals that have touched the plant can cause severe allergic dermatitis in some individuals. There is usually a latent period of about 12 - 24 hours from the moment of contact, this is followed by a reddening and severe blistering of the skin. Even plant specimens 100 or more years old can cause problems[1].

Edible uses

There are no edible uses listed for Rhus diversiloba.

Material uses

The leaves are rich in tannin. They can be collected as they fall in the autumn and used as a brown dye or as a mordant[2].

An oil is extracted from the seeds[3]. It attains a tallow-like consistency on standing and is used to make candles. These burn brilliantly, though they emit a pungent smoke[3]. The supple stems are used as the warp in basket making[4]. Slender stems are used as circular withes in basket making[5].

An excellent black dye is obtained by exposing the sap to air[4].

Unknown part

Basketry
Dye
Ink
Mordant
Oil

Medicinal uses(Warning!)

Western poison oak was employed medicinally by some native North American Indian tribes who used it to treat various complaints[5]. In view of the potential toxicity of the plant, extreme caution is advised in any use of it. See the notes above on toxicity.

A leaf has been swallowed in the spring as a contraceptive[5]. A tincture of the fresh leaves has been used in the treatment of eczema and skin diseases[3]. It is also used in the treatment of warts, ringworm etc[4]. A poultice of the fresh leaves has been applied to rattlesnake bites[5]. The leaf buds have been eaten in the spring in order to obtain immunity from the plant poisons[5] A moxa of the plant has been used in the treatment of warts and ringworm[5]. The juice of the plant has been used as a treatment for warts[5].

An infusion of the dried roots has been taken in order to give immunity against any further poisoning[5]. A decoction of the roots has been used as drops in the eyes to heal tiny sores inside the eyelids and to improve vision[5].

Unknown part

Antidote
Contraceptive
Ophthalmic
Warts

Ecology

Ecosystem niche/layer

Ecological Functions

Nothing listed.

Forage

Nothing listed.

Shelter

Nothing listed.

Propagation

Seed - best sown in a cold frame as soon as it is ripe. Pre-soak the seed for 24 hours in hot water (starting at a temperature of 80 - 90c and allowing it to cool) prior to sowing in order to leach out any germination inhibitors[6]. The stored seed also needs hot water treatment and can be sown in early spring in a cold frame[6]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts.

Cuttings of half-ripe wood, 10cm with a heel, July/August in a frame[6]. Root cuttings 4cm long taken in December and potted up vertically in a greenhouse. Good percentage[7][6].

Suckers in late autumn to winter[6].

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



Cultivation

Succeeds in a well-drained fertile soil in full sun[6]. Plants do not require a rich soil[8].

The young growth in spring can be damaged by late frosts. Plants have brittle branches and these can be broken off in strong winds[6]. Plants are also susceptible to coral spot fungus[8]. This species is closely related to R. toxicodendron[9]. Many of the species in this genus, including this one, are highly toxic and can also cause severe irritation to the skin of some people, whilst other species are not poisonous. It is relatively simple to distinguish which is which, the poisonous species have axillary panicles and smooth fruits whilst non-poisonous species have compound terminal panicles and fruits covered with acid crimson hairs[9][3]. The toxic species are sometimes separated into their own genus, Toxicodendron, by some botanists[6]. Plants in this genus are notably resistant to honey fungus[6].

Dioecious. Male and female plants must be grown if seed is required.

Crops

Problems, pests & diseases

Associations & Interactions

There are no interactions listed for Rhus diversiloba. 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 Rhus diversiloba.

Descendants

Cultivars

Varieties

None listed.

Subspecies

None listed.

Full Data

This table shows all the data stored for this plant.

Taxonomy
Binomial name
Rhus diversiloba
Genus
Rhus
Family
Anacardiaceae
Imported References
Edible uses
Medicinal uses
[5][3][4]
Material uses & Functions
[2][3][4][5]
Botanic
[8][10][6]
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
5
Heat Zone
?
Water
moderate
Sun
full sun
Shade
no shade
Soil PH
acid, neutral, alkaline
Soil Texture
sandy, loamy, clay
Soil Water Retention
well drained
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
    deciduous
    Herbaceous or Woody
    woody
    Life Cycle
    perennial
    Growth Rate
    ?
    Mature Size
    2.5 x meters
    Fertility
    self sterile
    Pollinators
    Bees
    Flower Colour
    ?
    Flower Type
    dioecious











    References

    1. ? Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J [Illustrated Flora of North Central Texas] Botanical Research Institute, Texas. (1999-00-00)
    2. ? 2.02.1 Buchanan. R. A Weavers Garden. ()
    3. ? 3.03.13.23.33.43.5 Grieve. A Modern Herbal. Penguin ISBN 0-14-046-440-9 (1984-00-00)
    4. ? 4.04.14.24.34.4 Balls. E. K. Early Uses of Californian Plants. University of California Press ISBN 0-520-00072-2 (1975-00-00)
    5. ? 5.005.015.025.035.045.055.065.075.085.095.10 Moerman. D. Native American Ethnobotany Timber Press. Oregon. ISBN 0-88192-453-9 (1998-00-00)
    6. ? 6.06.16.26.36.46.56.66.76.86.9 Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press ISBN 0-333-47494-5 (1992-00-00)
    7. ? Sheat. W. G. Propagation of Trees, Shrubs and Conifers. MacMillan and Co (1948-00-00)
    8. ? 8.08.18.2 Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray (1981-00-00)
    9. ? 9.09.1 F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press (1951-00-00)
    10. ? Munz. A California Flora. University of California Press (1959-00-00)


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    Facts about "Rhus diversiloba"RDF feed
    Article is incompleteYes +
    Article requires citationsNo +
    Article requires cleanupYes +
    Belongs to familyAnacardiaceae +
    Belongs to genusRhus +
    Has common nameWestern Poison Oak +
    Has drought toleranceIntolerant +
    Has fertility typeSelf sterile + and Bee +
    Has flowers of typeDioecious +
    Has hardiness zone5 +
    Has lifecycle typePerennial +
    Has material partUnknown part +
    Has material useBasketry +, Dye +, Ink +, Mordant + and Oil +
    Has mature height2.5 +
    Has medicinal partUnknown part +
    Has medicinal useAntidote +, Contraceptive +, Ophthalmic + and Warts +
    Has search namerhus diversiloba + and x +
    Has shade toleranceNo shade +
    Has soil ph preferenceAcid +, Neutral + and Alkaline +
    Has soil teclayture preferenceClay +
    Has soil teloamyture preferenceLoamy +
    Has soil tesandyture preferenceSandy +
    Has soil water retention preferenceWell drained +
    Has sun preferenceFull sun +
    Has taxonomy nameRhus diversiloba +
    Has water requirementsmoderate +
    Is deciduous or evergreenDeciduous +
    Is herbaceous or woodyWoody +
    Is taxonomy typeSpecies +
    Tolerates nutritionally poor soilNo +
    Uses mature size measurement unitMeters +