|Species||Torreya californica Torr. - California nutmeg|
Common Names: (USDAFS, 2003)
Figure 1. Torreya californica in Mendocino County, California. Photo by Anica Williams (2003).
Description of Taxonomy:
The following description of the classification of the Torreya Californica was taken from the same source (unless otherwise noted), Hyperdictionary, 2003. The kingdom Plantae is comprised of all living or extinct plants and the subkingdom Tracheobionta includes all vascular plants. The subdivision Spermatophyta is comprised of seed plants, i.e. plants that reproduce by seeds. Coniferophyta is the division that includes conifers (cone-bearing), gymnosperms, dating from the Carboniferous period. The class Pinopsida includes most conifers and the order Taxales is coextensive with the family Taxaceae. The family Taxaceae includes the Yew family. The genus Torreya Arnott “is characterized by furrowed bark and whorled or opposite and drooping branches and linear, evergreen, fetid foliage, with pale bands of stomata on the lower surface, the upper dark green, with the margins curved under” (Peattie, 1991, p. 290). The species Torreya californica is a small to moderate sized tree native and endemic (limited) to California (Calflora, 2003).
Description of Species:
(Source: Whitney, 1992; unless otherwise noted)
The Torreya californica
is a strongly aromatic tree with a conical or rounded crown and rows
of slender, spreading branches (Figure 1). It ranges in height from 16
to 70 feet (5 - 21m), with a diameter of 8 inches to 2 feet (0.2 - 0.6m),
The needles of the T. californica are evergreen, alternate and spreading in 2 rows (Figure 2). They are 1 to 2 ¾ inches (2.5 – 7 cm) long and are less than 1/8 inches (3 mm) wide with long sharp points at the tips. The needles are mostly paired, flattish, slightly curved, stiff and almost stalkless at base. The needles are shiny dark green above and green with two narrow whitish lines beneath.
The bark is gray-brown and thin with irregular fissures into narrow scaly ridges. The wood is light, soft and yellow (Munz and Keck, 1959). It has a fragrance similar to sandalwood and when freshly cut it can make ones skin itch (Murray, 1985). The twigs are mostly paired and slender. They are yellow-green and turn reddish brown.
T. californica is one of the few native conifers that are dioecious, meaning the male and female flowers are on separate trees (VTFD, 2003). The seeds are 1 to 1 ½ inches (2.5 – 4 cm) long. They are an obovoid-ellipsoid shape with a fleshy green outer layer (Figure 3). When the seed is ripe the outer layer becomes streaked with purplish markings and sheds. The seeds inner layer is yellow-brown, thick-walled, resinous, endosperm copious and stalkless. The seeds mature in two seasons and are scattered and single on leafy twigs. The seed resembles the aromatic and deeply folded seed coat, to those of the unrelated commercial spice, nutmeg (Myristica fragrans), hence the name California nutmeg. Male or pollen cones are 3/8 inches (10 mm) long. They are elliptical, pale yellow and single at leaf bases.
The T. californica grow in mixed evergreen forest habitats, with Douglas fir, yellow pine, redwood, western hemlock, grand fir, tanoak and California laurel (Whitney, 1992). They are usually found growing along mountain streams and especially in cool deeply shady slopes and canyon bottoms. They are also found on exposed slopes with chaparral and on shaded slopes in the belt between redwood pockets and chaparral (Howell, 1949). The T. californica is rare and widely scattered with a relatively low density of individual species in a given area (Maxwell, 1992). Seed dispersal is limited to a short distance from the parent tree because the seeds are too large and heavy for wide dispersal (Murray, 1985). Trees of both sexes have to grow near one another in order to produce viable seeds.
Figure 3. Seed of the Torreya californica, Yosemite National Park, California (1955). Photo by Charles Webber © 1998 California Academy of Sciences (CalPhotos, 2003).
Other Uses: It is sometimes planted in landscape gardening as an ornamental plant but the pungent odor of the leaves makes it less attractive. The seed oil has the
potential to be used in cooking, as it is similar in quality to olive and pine nut oil (UADAFS, 2003). Apparently, seeds of the related Asian species, Torreya
nucifera, are harvested and made into a high-quality cooking oil.
The largest registered T. californica is on the American Forests’ National Register of Big Trees list and is found in Swanton, Santa Cruz County, California, Figure 4 (American Forests, 2003). In 1992, the last time it was measured, its height was 96 feet, its circumference was 251 inches and its spread was 68 feet, it is probably bigger now (American Forests, 2003). Up until 1983 there was an even bigger T. californica registered with the AFA National Register of Big Trees growing near Fort Bragg in Mendocino County, California (Murray, 1985). It stood 141 feet high and had a girth of 14 feet 10 inches before it was cut down by timber thieves, in 1983 (Murray, 1985).
The genus Torreya is an old taxon, with shoot and leaf fossil material found in Yorkshire, England and in Bornholm, Denmark from the Middle Jurassic Period (170 million years ago) (Maxwell, 1992). Earlier fossils, from the Cretaceous Period (144 to 65 million .years ago), have been found in North Carolina and Colorado (Maxwell, 1992). In the Tertiary Period (65 to 2 million years ago) the genus was found in the western United States and Continental Europe (Maxwell. 1992). By the Pliocene epoch (5.1 to 2 million years ago) it had spread into central and southern Europe and central Japan. During this pre-Pleistocene period the genus Torreya was a widespread circumpolar flora with a circumboreal distribution, found in the high latitudes (Howell, 1949).
“Both Florin (1963) and Barbour and Major (1988) attribute the eventual shrinkage of range [of the g. Torreya] to “deterioration” of the climate leading up to the Pleistocene glaciations, [1.8 million to 11,000 years ago]” (Maxwell, 1992, p.16). With this theory the genus Torreya would be a climatic relict, since its distribution may have been affected by this past changes in climate. The Ice Age of the Pleistocene caused the flora to migrate further south from its previous locations in the north to southern Europe, Asia and North America. Eventually the genus disappeared in Europe and was limited to its present distribution in Asia and North America.
There is further speculation as to the reasons for the sparse and
disjunct distribution of Torreya. According to Stebbins and
Major (1965) Torreya is classed as a paleoendemic, meaning
that its status as an endemic is the result of shrinkage of a previously
widespread distribution (Maxwell, 1992). According to Fiedler and
Ahouse (1991) the causes of its rarity are “1) earth history, evolutionary
history and taxon age; 2) population dynamics, taxon ecology and
reproductive biology; and 3) coevolution, stochasticity and taxon
genetics” (Maxwell, 1992, p. 25). These factors help to explain
the elusive distribution of the Torreya genus.
The distribution of the species Torreya californica is limited to California, i.e. it is endemic to California. The species is restricted to two distinct areas, the Coast Ranges (mountains of central and northern California) and the western slope of the Sierra Nevada foothills, with no connecting link between the two ranges (Figure 5). On the coast they are found at elevations up to 3600 ft, from Mendocino to Santa Cruz counties (Peattie, 1991). In the Sierra Nevada foothills it is found at elevations up to 6000 feet, from Tulare to Tehama counties (Peattie, 1991). Precipitation is a limiting factor for the distribution of the T. californica because they aren’t found in the arid regions of southern California (Barbour and Major, 1977). They inhabit areas with a mean annual rainfall of 46.4 inches (Maxwell, 1992).
is an old taxon and its seeds are by far the largest to have survived
and reproduced for at least 170 million years (Maxwell, 1992). The genus
Torreya was once widespread throughout the Northern Hemisphere
with fossil records showing it in Europe, Greenland, Alaska, British Columbia,
Oregon, Colorado, Virginia and North Carolina (Stein, 2000). This genus
now has an extremely spatially disjunction distribution. The reason for
its present discontinuous pattern may be due to the inability of the genus
to compete with newer life forms, making it an evolutionary relict. One
cause for the genus’ inability to compete may be due to its limited dispersal
because of its large seed size.
In total there are five species and one variety under the genus Torreya (Burke, 1975). The genus Torreya is now only found in parts of eastern Asia and two small and distinct enclaves in North America, California (T. californica) and a small range in northern Florida (T. taxifolia) (Burke, 1975). T. taxifolia is an endangered species and the current hypothesis for its decline is a result of fungal infestation attacking trees under conditions of increased environmental stress (Schwartz and Hermann, 2003). T. nucifera is found in central Honshu, Japan and possibly Korea (Burke, 1975). The species T. grandis is found in eastern China and T. jackii is found only in Zhejiang province, China (Maxwell, 1992). The one variation, T. grandis var. fargesii Silba, occurs in northeast China and Burma (Maxwell, 1992).
The distribution of the yew family, Taxaceae, is also mostly limited to the Northern Hemisphere. It’s found in Europe (Britain to N Iran), Asia (USSR, Korea, Japan, China, Taiwan India, Burma, Vietnam, Philippines), North America ( Arkansas to California, eastern Canada, eastern USA, Florida, Mexico, Guatemala, El Salvador) and South America (Earle, 2002). The current distribution pattern of Taxaceae may be the result of a relicted distribution from the Luarasia landmass.
American Forests. 2003. National Register of Big Trees, Torreya Californica page. [Online]. Available: http://www.americanforests.org/resources/bigtrees/register.php?details=2515
Barbour, M. and J. Major. 1977. Terrestrial Vegetation of California. New York: John Wiley and Sons.
Beck, C. 1988. Origin and Evolution of Gymnosperms. New York: Columbia Press.
Burnie, D. 1994. Concise Encyclopedia of Nature. New York: Dorling Kindersley.
Earle, C. 2002. Gymnosperm Database, Taxaceae Page. [Online]. Available: http://www.botanik.uni-bonn.de/conifers/ta/index.htm
Hyperdictionary. 2003. [Online]. Available: http://www.hyperdictionary.com
Maxwell, Andrew. 1992. Mapping and habitat analysis of the California endemic tree, Torreya californica, in Marin County. San Francisco, CA.
Munz, P. and Keck, D. 1959. A California Flora. Berkeley: UC of Cal Press.
Murray, Marshall. June 1982. Hunting the California Nutmeg. American Forests. 91 40-41.
Pant, D. August 2000. Inclusion of Taxaceae in a Separate Order, Taxales. Current Science. 79 (3) 278-279. [Online]. PDF Available: http://tejas.serc.iisc.ernet.in/~currsci/aug102000/op181.pdf
Peattie, D. 1991. A Natural History of Western Trees. Boston: Houghton Mifflin Co.
Schwartz, M. and Hermann, S. 2003. Environmental Change and the Florida Torreya. [Online]. Available: http://biology.usgs.gov/s+t/noframe/j218.htm
Stein, W. 2000. Torreya Arn., torreya. Woody Plant Seed Manual. [Online]. PDF Available: http://wpsm.net/Torreya.pdf
U.S. Department of Agriculture (USDA), Natural Resources
Conservation Service. 2003. Plant Profile: Torreya californica
Torr. [Online]. Available:
U.S. Department of Agriculture Forest Service (USDAFS), 2003. Index of Species Information, Species: Torreya californica. [Online]. Available: http://www.fs.fed.us/database/feis/plants/tree/torcal/all.html
Virginia Tech Forestry Department (VTFD). 2003. California nutmeg Taxaceae Torreya californica. [Online]. Available: http://www.cnr.vt.edu/dendro/dendrology/syllabus/tcalifornica.htm
Whitney, Stephen. 1992. The Audubon Society Nature Guides: Western Forests. New York: Alfred A. Knopf.