+-----------------------------------------------------------------------+
| ## tanoak {#tanoak .Title-Header}                                     |
+-----------------------------------------------------------------------+
| *Lithocarpus densiflorus* (Hook. & Arn.) Rehd.                        |
+-----------------------------------------------------------------------+
| Plant Symbol = LIDE3                                                  |
+-----------------------------------------------------------------------+

Contributed by: USDA NRCS National Plant Data Center

### ![](media/image2.jpeg){width="3.245833333333333in" height="2.1756944444444444in"}

# Alternate Names

Tan oak, tan bark oak

#####  

# Uses

*Ethnobotanic*: Historically, acorns were the most important staple
plant food for Native American groups in the coastal ranges of
California. Native Californians harvested, and still harvest today,
several species of acorns including tanoak, coast live oak (*Quercus
agrifolia*), canyon oak (*Q. chrysolepsis*), black oak (*Q. kellogii*),
and valley oak (*Q. lobata*). California tribes are estimated to have
harvested from 500 to 2000 pounds of acorns per family per year (Hoover
1977). A single tanoak tree can produce over 200 pounds of acorns in a
good year and produces at least a partial crop every year (Baumhoff
1963).

Tanoak acorns were the preferred acorns for the Salinan, Costanoan,
Pomo, Yurok, Hoopa, and other groups residing within the trees range
(Baumhoff 1963; Merriam 1967; Heizer & Elsasser 1980). The ripe acorns
are harvested in the fall. They were spread out in the sun to dry and
then stored in baskets or storage bins. Many tribes constructed outdoor
storage bins, either above or below ground, to protect the dried acorns
from robbing squirrels and chipmunks. The Salinan built outdoor acorn
granaries on the ground next to their homes (Mason 1912). The granaries
were constructed in a basket-like fashion from white willow twigs that
were then covered with grass. The Pomo used tanoak leaves to line
aboveground bins that they constructed from redwood (*Sequoia*
*sempervirens*) boughs (Hoover 1977). The Costanoan and Chumash stored
acorns in baskets made from interlaced white willow twigs (Brusa 1975).
The baskets were about 1 m in diameter at the bottom and sloped up
gradually inward into a cone about 0.5 m with a 0.5 m opening. Hollow
tree trunks also served as storage bins (Hoover 1971).

The acorns were pounded into flour as needed. Stone, bedrock, and wooden
mortars were used to crush the acorns into a meal. Sometimes the acorns
were soaked overnight to help crack open the shells. After soaking, the
acorns were removed from the shells and spread out onto open-work
baskets to dry. The Salinan cracked open the acorns individually using a
small, hard stone hammer and then set them out in the sun to dry (Mason
1912). The dried acorns were then placed into a stone, bedrock, or
wooden mortar and pulverized into flour using a long pestle. Some tribes
used a hopper mortar basket (a bottomless basket either glued with tar
to the stone mortar or held down with the legs) to keep the pounded
flour from bouncing up out of the mortar. Mason (1912) notes
observations of remnant pitch or asphaltum circles surrounding mortar
depressions within the Salinan area. After pounding, acorn flour must be
leached to remove the tannic acid. There are various methods for
completing this step, but they all include pouring water through the
meal repeatedly until all traces of the bitter tannins are washed away.
The Salinan placed the finely pounded flour into a specially made
leaching basket. The basket was woven closely enough to hold the meal
but to allow the leaching water to percolate through (Mason 1912).

The majority of the California tribes, including the Costanoan, Yokuts
and Luiseño peoples, leached acorn flour by using carefully constructed
basins of clean sand near a stream or river. The flour was leached many
times by pouring the water over a bundle of leaves to keep the water
from splashing sand into the meal. Other tribes made leaching frames
from branches of incense cedar. The cedar leaves kept the meal from
washing away while imparting a spicy flavor to the meal (Murphey 1959).
Another leaching method was to bury the whole acorns in the bed of a
running stream and leaving them for as long as a year (Merriam 1967).

The finely pulverized acorn meal was mixed with water and cooked in a
special watertight cooking basket by placing hot, round stones that had
been heated in the fire into the basket. The acorn mixture was stirred
constantly to keep the rocks rolling around and prevent them from
burning the basket. The meal was cooked in this manner to make porridge
and also a thick soup called *atole*. The cooked mixture could be used
to make pancakes and breads by pouring it onto a hot, flat rock that
served as a griddle. The Salinan baked acorn bread in an earth-oven and
made acorn cakes about 8cm in diameter by wrapping them between two
layers of grass and cooking them overnight (Mason 1912). The Pomo used
to wrap loaves of acorn bread dough in leaves and place it in the coals
of a fire to cook (Goodrich et al. 1990). The Yurok made a dry form of
acorn bread, baked on hot stones, which kept for a month or more
(Merriam 1967).

Tanbark acorns were also used for medicinal purposes such as treating
coughs. A single acorn was popped into the mouth and sucked on like a
cough drop. The tannins are said to help sooth the throat. Some
California tribes made a type of penicillin from acorn meal (Murphey
1959). Moist meal was wrapped and allowed to sit until it developed a
moldy film. Then the film was peeled off into a roll, which was stored
in a damp place until needed. Pieces of the mold were placed upon boils
and other sores to draw out inflammation. The Coastanoan made an
infusion from the bark that they used as a medicinal wash for sores on
the face and as a mouthwash to treat loosened teeth and toothaches
(Bocek 1984).

Whole tanbark acorns with their caps can be strung together to make a
musical instrument that is played by twirling it in a special way.

The Wintu made candy from the gum-like sap that they gathered in the
fall (Dubois 1935). The Wintu and other tribes used the soot from burnt
oak galls to make tattoos (Knudtson 1988).

*Wildlife*: Tanoaks are important for cover and are used for resting,
hiding, and nesting by many wildlife species (McMurray 1989). The trees
provide cover for northern flying squirrels (*Glaucomys sabrinus*),
dusky-footed woodrats (*Neotoma fuscipes*), arboreal salamanders
(*Aneides lugubris*), and black salamanders (*Aneides flavipunctatus*).
House wrens (*Troglodytes aedon),* northern flickers (*Colaptes
auratus*), downy woodpeckers (*Picoides pubescens*), red-breasted
nuthatches (*Sitta Canadensis*), white-breasted nuthatches (*Sitta
carolinensis*), and brown creepers (*Certhia Americana*) nest in
cavities in tanoak trees.

Mule deer (*Odocoileus hemionus*) graze on tanoak leaves and acorns.
Tanoak acorns are a source of food for black bears (*Ursus americanus*),
chipmunks (*Eutamias spp.*), California ground squirrels (*Spermophilus
beechyi*), Douglas squirrels (*Tamiasciurus douglasi*), pocket gophers
(*Thomomys bottae*) and black-tailed deer (*Odocileus hemionus*). The
acorns were once relished by grizzly bears (*Ursus arctos*), the state
emblem of California, which have been extinct in this state since 1924
(Storer & Usinger 1963). Birds that rely on tanoak acorns as a source of
food include the Steller's jays (*Cyannocita* stelleri), band-tailed
pigeons (*Columba fasciata*), varied thrushes (*Ixoreus naevius*) and
acorn woodpeckers (*Melanerpes formicivorus*).

*Livestock*: Ground acorns are sometimes added to chicken feed. Tanoak
is considered of low forage value for livestock because of its low
palatability due to tannin content. When cattle and other livestock
consume tanoak, it is an indication of overgrazing, as the animals will
generally only resort to this food source after higher quality forage
has been consumed (McMurray 1989).

*Erosion control*: Tanoaks may be used for erosion control on sites that
experience frequent disturbance. The trees help to stabilize soils as
they have an extensive root system with a deep taproot and they quickly
reestablish after disturbance through sprouting from a lignotuber, which
is an underground regenerative organ (McMurray 1989).

*Other*: Tanoak wood is of high quality, being of good strength and
hardness with a fine grain, however the wood is not widely used because
of limited supply. Tanoak wood has been used for a variety of purposes
including flooring, paneling, decking, plywood, garden tools, baseball
bats, and firewood. The bark has high tannin content and was once used
extensively by industry in California for curing leather.

# Status

Please consult the PLANTS Web site and your State Department of Natural
Resources for this plant's current status (e.g. threatened or endangered
species, state noxious status, and wetland indicator values).

# Description

######## General: Oak family (Fagaceae). Tanoak is an evergreen hardwood tree or shrub native to the west coast ranges from Southern Oregon to Southern California. The plants can reach 20 to 45 meters in height with the stems of large trees reaching up to 1 meter in diameter. The form and size of tanoak is variable depending on the environment. Taller forms generally occur in shady forests and shorter forms in open areas where sunlight is more abundant. However, the trees can have a shrub-like form with multiple stems when access to light is prevented, such as when growing in a dense forest understory. Mature trees growing in a more open forest have a single, short trunk with horizontal branches. 

######## 

######## The thick, leathery evergreen leaves are oblong in shape with pointed tips (4 to 10 cm long). The leaves have noticeable parallel side veins on the undersides that are evenly spaced and run from the central vein of the leaf ending in a pointy tooth at the leaf margin. New leaves are covered with reddish-brown hairs, which turns whitish as they mature. Older leaves are a smooth green on top with lightly pubescent gray-green below. The evergreen leaves remain on the tree about 3 to 4 years before they are shed. The light reddish-brown bark develops deep fissures as the trees age. Large clusters of tiny white flowers bloom in the summer months in the leaf axils of the current seasons growth. The flowers are erect catkins and have an odor that is not pleasant. The acorns are from 2.5 to 5 cm long with a diameter of about 1.5 to 1.8 cm and grow singly or in cluster. Tanoak acorns have hairy, rather than scaly caps of the true oak. Acorns ripen in the fall of the second season. 

*Distribution*: Tanoak occurs on fertile mountain slopes and ridges
below 1200 meters in the Coast Ranges from the Santa Inez Mountains in
Southern California, to the Cascade Ranges in Southwestern Oregon. For
current distribution, please consult the Plant Profile page for this
species on the PLANTS Web site.

*Habitat*: The tree form is a major part of the coastal redwood forest,
Douglas fir forest, and mixed evergreen forest while the shrub form is a
component of chaparral communities.

# Adaptation

Tanoak is adapted to cool coastal areas with mild temperatures and
little summer rainfall. The plants do not do well in interior valleys
and areas of extreme temperatures. Tanoaks grow best in deep, fertile
soils but are also known to grow well on stony or shallow soils. The
trees prefer well-drained loam to gravelly soils.

# Establishment

The Kashaya Pomo name for tanoak means "beautiful tree" (Goodrich et al.
1990). Tanoak is an attractive tree that is shade tolerant.

Tanoak can be easily propagated by seed. Use only fresh seeds, as the
seeds do not retain viablity. The seeds of tanoak require no
pretreatment and germinate quickly. Tanoak acorns germinate faster if
they are planted with their point facing upward in the soil (McMurray
1989). The seeds may be directly sown into the ground or planted into
flats or pots using a light soil mixture or peat moss. If flats are used
it is necessary to transfer the seeds into pots or the ground once they
have germinated. Pots should be of the kind that are long and deep to
allow for the taproot to develop. Set the seeds or seedlings into a
carefully chosen spot keeping in mind that they can be long lived, with
an average age of about 180 years and a maximum to 400 years. Seedlings
do best in a moist area with partial shade. Do not plant in areas with
frequent irrigation. Give seedlings an occasional deep watering until
established.

# Management

Tanoak trees need to be carefully pruned while young in order to develop
into a nicely shaped, dense, well-branched tree. The trees should be
placed in a spot where they will be protected from extreme temperatures
and hot winds, which may burn the leaves during hot, dry weather.
Established trees should not be watered unless there are severe drought
conditions.

# Pests and Potential Problems

Tanoak is among the several species in northern and central California
that have been affected by the *Phytophthora* fungus, in what is called
"sudden oak death syndrome." The disease is easily spread by beetles
attracted to the sap of the infected trees. Contact with infected roots
and wood, and infected soil may be transported on tools, tires or shoes
(Brenzel 2001). To keep trees healthy, apply a thick layer of mulch to
the root zone area beneath the crown and do not garden or disturb this
area in any way. Also avoid frequent irrigation, prune only from June to
September (when the fungus and insects are less active), and fertilize
if the tree shows signs of deficiency (Švihra et al. 2001). Prunings and
firewood from infected trees should be enclosed in heavy, clear plastic
for 6 months in order to trap and kill beetles that may emerge and
infect nearby living trees (Brenzel 2001). Other pests include aphids,
greedy scale, mealybug, oak scale and white fly.

# Cultivars, Improved, and Selected Materials (and area of origin)

There are two varieties of *Lithocarpus densiflorus*: var. *echinoides*
is a shrub that is a component of chaparral communities, and var.
*densiflora* is a tree form which grows in mixed coastal evergreen
forest communities. Contact your local Natural Resources Conservation
Service (formerly Soil Conservation Service) office for more
information. Look in the phone book under "United States Government."
The Natural Resources Conservation Service will be listed under the
subheading "Department of Agriculture."

# References

Baumhoff, M.A. 1963. *Ecological determinants of Aboriginal California
populations.* University of California Press, Berkeley & Los Angeles,
California. 235 pp.

Bocek, B.R. 1984. *Ethnobotany of Costanoan Indians, California, based
on collections by John P. Harrington.* Economic Botany, Vol. 38, No. 2.
Pp. 240-255.

Brenzel, K.N., Editor 2001. *Western garden book*. Sunset Publishing
Corp., Menlo Park, CA. 768 pp.

Brusa, B.W. 1975. *The Salinan Indians and their neighbors.* Naturegraph
Publishers, Inc., Happy Camp, California. 95 pp.

Dubois, C. 1935. *Wintu ethnography.* University of California
Publications in American Archeology and Ethnology. Vol. 36, No. 1.

Goodrich, J., C. Lawson & V.P. Lawson 1980. *Kashaya Pomo Plants*.
Heyday Books, Berkeley, California. 171 pp.

Heizer, R.F. & A.B. Elsasser 1980. *The natural world of the California
Indians*. University of California Press, Berkeley & Los Angeles,
California. 271 pp.

Hoover, R.L. 1971. *Food plants of the California Indians*. Pacific
Discovery Vol. 24, No. 3. Pp.11-17.

Hoover, R.L. 1977. *California Indian uses of native plants.* In: D. R.
Walters, M. McLeod, A.G. Meyer, D.Rible, R O. Baker, & L. Farwell.
*Native plants: A viable option.* Special Publication No. 3, California
Native Plant Society, Berkeley, California. Pp.128-162.

Knudtsen, P.M. 1988. *The Wintu Indians of California.* Naturegraph
Publishers, Inc. Happy Camp, California. 92 pp.

Labadie, E.L. 1978. *Native plants for use in the California landscape.*
Sierra City Press, Sierra City, California. 248 pp.

Lenz, L.W. 1956. *Native plants for California gardens.* Abbey Garden
Press, Pasadena, California. 166 pp.

Merriam, C.H. 1967. *Ethnological notes on California Indian Tribes.*
Compiled & Edited by R.F. Heizer. Reports of the University of
California Archaeological Survey, No. 68, Parts II & III. Pp 167-448.

McMurrray, N.E. 1989. *Lithocarpus densiflora*. In: U.S. Department of
Agriculture, Forest Service, Rocky Mountain Research Station, Fire
Sciences Laboratory 2001, May. *Fire Effects Information*

*System*, \[Online\]. Available: <http://www.fs.fed.us/database/feis/>.
\[20 October 2001\].

Murphey, E.V.A. 1959. *Indian uses of native plants.* Mendocino County
Historical Society, Fort Bragg, California.

81 pp.

Storer, T.I. & R.L. Usinger 1968. *Sierra Nevada Natural History*.
University of California Press, Berkeley & Los Angeles, California. 374
pp.

Švihram P., J.K. Palkovsky, & A. J. Storer 2001. *Recommendations for
the management of oaks in areas affected by sudden oak death.*
University of California Cooperative Extension. 2001. *Marin County
Sudden Oak Death Publications,* \[Online\]. Available:

<http://cemarin.ucdavis.edu/publications.html>. \[15December 2001\].

Webber, C. 1998. *Lithocarpus densiflora*. California Academy of
Sciences. Digital Library Project, University of California, Berkeley,
\[Online\]. Available:
[http://www.calflora.org](http://www.calflora.org/). \[18November
2001\].

##### 

# Prepared By: 

######## Diana L. Immel

USDA, NRCS, National Plant Data Center, c/o Plant Sciences Department,
University of California, Davis, California

# Species Coordinator: 

##### *M. Kat Anderson* 

##### USDA, NRCS, National Plant Data Center, c/o Plant Sciences Department, University of California, Davis, California 

##### Edited: 29jan02 jsp; 21may03 ahv; 060802 jsp

For more information about this and other plants, please contact your
local NRCS field office or Conservation District, and visit the PLANTS
Web site\<[http://plants.usda.gov](http://plants.usda.gov/)\> or the
Plant Materials Program Web site
\<[http://Plant-Materials.nrcs.usda.gov](http://Plant-Materials.nrcs.usda.gov/)\>

*The U.S. Department of Agriculture (USDA) prohibits discrimination in
all its programs and activities on the basis of race, color, national
origin, sex, religion, age, disability, political beliefs, sexual
orientation, and marital or family status. (Not all prohibited bases
apply to all programs.) Persons with disabilities who require
alternative means for communication of program information (Braille,
large print, audiotape, etc.) should contact USDA\'s [TARGET
Center](http://www.usda.gov/oo/target.htm) at 202-720-2600 (voice and
TDD).*

*To file a complaint of discrimination write USDA, Director, Office of
Civil Rights, Room 326-W, Whitten Building, 14th and Independence
Avenue, SW, Washington, DC 20250-9410 or call 202-720-5964 (voice or
TDD). USDA is an equal opportunity provider and employer.*

*Read about [Civil Rights at the Natural Resources Convervation
Service](http://www.nrcs.usda.gov/about/civilrights/).*