
Torreya californica
Torreya californica
Safety & Hazards
None known
Cultivation Details
Torreya californica is a fairly cold-hardy tree, able to tolerate temperatures falling to between -17.7°c and -12.2°[1]. One report says that trees are only hardy in the milder parts of Britain[2], whilst another says that trees are hardy in Britain at least as far north as Edinburgh[3]. This species is the only member of the genus that is fully adapted to cool maritime climates. It can actually grow faster in such a position than it does in its native habitat[3]. Succeeds in ordinary garden soil, tolerating some lime[2]. Undemanding as to the soil pH[3]. Dislikes wind exposure[3]. Requires a sheltered position and either high humidity or a moist riverside soil[3]. Tolerates woodland shade very well[3]. Species in this genus are generally adapted to growing in primary woodland. The seedlings are very shade tolerant, establishing well in the deeper shade of a woodland and then growing up to the light. They can sometimes be found growing in secondary vegetation, but they do not usually persist, being outcompeted by other, more light-tolerant species[1]. The tree produces new sprouts from the roots, bole, and root crown following damage to above-ground portions of the tree. Numerous sprouts are produced at the base of the parent tree, although only one sprout usually survives after several years of growth[4]. Usually slow growing, though trees can occasionally increase by up to 60cm in a year[5]. The bruised leaves release a powerful resinous smell[6]. The fruits are also aromatic[6]. The seed takes two summers to mature[7]. Trees often crop well at Kew Gardens in the UK (hardiness zone 7 - 8), but there were no seeds formed in 1994[PFAF]. A tree in fairly deep shade at Kew was carrying a good crop of seeds in the summer of 1996[PFAF]. Plants are usually dioecious, but isolated female plants have been known to bear fruit in the absence of a pollinating male[8]. Plants are sometimes monoecious with dioecious branches. Male and female plants must usually be grown if seed is required. Torreya californica is a scattered understorey tree usually growing in moist and shady places in hilly to mountainous terrain dominated by tall conifers, especially Sequoia sempervirens, Picea sitchensis and Pseudotsuga menziesii. In the western valleys of the Sierra Nevada it is associated with angiosperms, mainly Acer spp., Cornus nuttallii, Platanus occidentalis, and Alnus rubra and here it strictly adheres to stream banks in steep canyons at altitudes around 1,200 m a.s.l. Its altitudinal range is from near sea level (but usually above 200 m) in the Coast Ranges to 2,500 m a.s.l. in the Sierra Nevada. On serpentine rock it becomes a stunted tree or shrub and occurs on north-facing slopes in coastal chaparral. It is capable of resprouting following disturbance such as fire although regrowth is slow[9].
Propagation
Seed - best sown as soon as it is ripe in a cold frame. Some of the seed should germinate in the following spring though much of it might take another 12 months. Stored seed requires a period of cold stratification and can take 18 months or more to germinate. Prick out the seedlings into individual pots as soon as growth is observed and grow them on in light shade in the greenhouse for at least the next couple of winters, making sure to pot them on into larger pots as and when required. Plant them out into their permanent positions in early summer when the plants are at least 20cm tall. Cuttings of half-ripe shoots in late summer[2]. Cuttings do not grow well[8]. Layering. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Torreya+californica>
Pollinators
Wind
References
- [1]The Gymnosperm Database — http://www.conifers.org/index.htm ↩︎A vast amount of information on conifers and families of gymnosperms.
- [2]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
- [3]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [4]Fire Effects Information System — http://www.feis-crs.org/feis/ ↩︎An on-line information site with comprehensive information on over 1,100 species of plant. Mainly developed to supply information on the effects of fire on plants and animals, it also contains a wealth of other information on the plants
- [5]Conifers in the British Isles. — Mitchell. A. F. · HMSO · 1975 · ISBN 0-11-710012-9 ↩︎A bit out of date (first published in 1972), but an excellent guide to how well the various species of conifers grow in Britain giving locations of trees.
- [6]Scented Flora of the World. — Genders. R. · Robert Hale. London. · 1994 · ISBN 0-7090-5440-8 ↩︎An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.
- [7]The Complete Trees of N. America. Field Guide and Natural History. — Elias. T. · Van Nostrand Reinhold Co. · 1980 · ISBN 0442238622 ↩︎A very good concise guide. Gives habitats, good descriptions, maps showing distribution and a few of the uses. It also includes the many shrubs that occasionally reach tree proportions.
- [8]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
- [9]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
- [10]Flora of N. America — http://flora.huh.harvard.edu/fna/ ↩︎An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.
- [11]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · Kampong Publications · 1990 · ISBN 0-9628087-0-9 ↩︎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.
- [12]Native American Ethnobotany — Moerman. D. · Timber Press. Oregon. · 1998 · ISBN 0-88192-453-9 ↩︎Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.
- [13]Tanaka's Cyclopedia of Edible Plants of the World. — Tanaka. T. & Nakao S. · Keigaku Publishing; Tokyo · 1976 · ISBN - ↩︎The most comprehensive list of edible plants I've come across. Only the briefest entry for each species, though, and some of the entries are more than a little dubious. Not for the casual reader.
- [14]Food Plants of the N. American Indians. — Yanovsky. E. · U.S. Depf of Agriculture. · ISBN - ↩︎A comprehensive but very terse guide. Not for the casual reader.
- [15]Plants for Human Consumption. — Kunkel. G. · Koeltz Scientific Books · 1984 · ISBN 3874292169 ↩︎An excellent book for the dedicated. A comprehensive listing of Latin names with a brief list of edible parts.
- [16]Manual of the Trees of N. America. — Sargent. C. S. · Dover Publications Inc. New York. · 1965 · http://www.biodiversitylibrary.org/ · ISBN 0-486-20278-X ↩︎Two volumes, a comprehensive listing of N. American trees though a bit out of date now. Good details on habitats, some details on plant uses. Not really for the casual reader. It can be downloaded from the internet.
- [PFAF]Plants for a Future — pfaf.org ↩︎