Taxaceae

Common names

The yew family (Hils 1993), [Chinese].

Taxonomic notes

Genera 5, species 17: mainly Northern Hemisphere (Hils 1993). The taxaceous conifers are generally regarded as being distinct from the other conifers; many authors have assigned them to a distinct Order, Taxales Knobl. 1890, and they have also been placed in a distinct Suborder, Taxineae Luerss. 1879, or have even been segregated at the Subclass rank as Taxidae Ehrend. ex Reveal 1996. Some authors have assigned Amentotaxus to a separate family (Amentotaxaceae Kud et Yamam. 1931), likewise Austrotaxus (Austrotaxaceae Nakai 1938) and Torreya (Torreyaceae Nakai 1938) (James L. Reveal e-mail 31-Dec-1998).

Description

Evergreen trees or shrubs, usually neither resinous nor aromatic (sharp- or foul-odored in Torreya), dioecious or monoecious. Bark scaly or fissured. Lateral branches well developed, similar to leading shoots; twigs terete, not densely clothed by leaves but ± ridged by decurrent leaf bases; longest internodes less than 1 cm; buds ± inconspicuous. Roots fibrous to woody. Leaves (needles) simple, persisting several years, shed singly, alternate [opposite], spirally arranged but often twisted so as to appear 2-ranked, linear to linear-lanceolate, decurrent; resin canals present or absent. Pollen cones maturing and shed annually, solitary or clustered, axillary on year-old branches, globose to ovoid, sporophylls bearing 2 - 16 microsporangia (pollen sacs); pollen ± spheric, not winged. Seed cones reduced to 1 - 2 ovules subtended by inconspicuous, decussate bracts, maturing in 1 - 2 seasons, axillary on year-old branches. Seeds 1 per "cone," erect, not winged, hard seed coat partially or wholly surrounded by a juicy, fleshy or leathery aril; cotyledons 2. Wood without resin ducts (Silba 1986, Hils 1993). All investigated species form a vesicular-arbuscular mycorrhiza (Brundrett 2008 and citations therein).

Range

Europe: Britain to N Iran. Asia: USSR, Korea, Japan, China, Taiwan, Himal, India, Burma, Vietnam, Philippines. New Caledonia. N America: SE AK to CA, E Canada, E USA, FL, Mexico, Guatemala, El Salvador. S America.

Big Tree

Oldest

Dendrochronology

Ethnobotany

Observations

Remarks

The family has been around quite a while. It includes at least one extinct genus, Kakahuia, reported from the Eocene and early Miocene of southern New Zealand (Pole 2007).

Citations

Brundrett, Mark. 2008. Mycorrhizal Associations: The Web Resource. mycorrhizas.info, accessed 2009.06.09.

See Also

Burns and Honkala (1990).

Canadian Forestry Service (1983).

Cheng Y., Chaw S., R. Nicholson and K. Tripp. 2000. Phylogeny of Taxaceae and Cephalotaxaceae genera inferred from chloroplast matK gene and nuclear rDNA ITS region. Molecular Phylogenetics and Evolution 14 (3): p. 353-365.

Farjon (1990).

Hosie (1969).

Little (1979).

Pilger (1903, 1916 and 1926).

Price (1990).

Florin, R. 1948. On the morphology and relationship of the Taxaceae. Botanical Gazette 110:31-39.

Krüssmann, G. 1972. Handbuch der Nadelgehölze. Berlin.