Callitris description

Foliage and cone on an ornamental specimen, species unknown [C.J. Earle, May-1999].

C. sulcata (Schmid 1981).

Callitris Ventenat 1808

Common Names

Australian cypress (Christiansen 2000), Cypress-pine (Wunderlin 1993).

Taxonomic notes

Syn: Frenela Mirbel 1825; Fresnelia Steudel; Leichardtia Sheph.; Pachylepis Brong.; Octoclinis F. Mueller 1858; Parolinia Endl. (Vidakovic 1991).

Callitris is a genus of 19 species. This treatment follows that given in the Flora of Australia (Hill 1998), which describes the 17 species native to Australia (the other 2 are in New Caledonia). I am not aware of any detailed modern taxonomic survey of the genus, the most recent being that by Garden (1957), but I have not yet seen the study by Adams and Simmonds (1987).

Description

Monoecious, evergreen trees or shrubs. Branches erect, spreading or fastigiate. Bark persistent, hard and compact (fibrous in C. macleayana). Branchlets appearing to consist of triangular or grooved-cylindrical joints owing to the decurrent leaf bases. Adult leaves scale-like, in alternating whorls of 3, decurrent for much of their length; free tip triangular in section and often appressed; dorsal surface rounded or keeled. Juvenile leaves in whorls of 4, triangular in cross-section, basally shortly decurrent below a spreading needle-like upper portion, in some species remaining on mature trees. Male cones ovoid, obovoid, oblong or cylindrical, solitary, paired or clustered at the ends of the branchlets, comprising numerous alternating, trimerous whorls of imbricate scales; each with 2-6 abaxial microsporangia; pollen spherical, not saccate. Female cones solitary or clustered on short lateral branches, comprising 2 whorls of 3 fertile scales with a reduced internode, to form a 6-merous cone (rarely 8 in C. macleayana and C. oblonga); outer whorl of scales often smaller than the inner; fertile scales each with 1-8 erect ovules and subtended by an adnate sterile bract which may form a dorsal protuberance; 10-30 mm diam.; globose to ovoid. Mature cones are persistent or deciduous. Below each scale are 1-8 seeds, oblong, with 1-3 wings (Harden 1990, Vidakovic 1991, Hill 1998). For the 7 species studied (Mehra and Koshoo 1956), 2n=22.

Range

Australia (all States) and New Caledonia; naturalized in USA: FL (Harden 1990, Wunderlin 1993).

Big Tree

C. macleayana grows up to 50 m in height and up to 1.5 m in diameter (Vidakovic 1991).

Oldest

Dendrochronology

Some work has been done. See, for example, Searson and Pearson (2001).

Ethnobotany

"A number of the more abundant species have been and still are widely cut for their durable and insect-resistant timber" (Hill 1998). Aboriginal Australians have used different species for diverse purposes, such as oars, spears, glues, and medicines (Christiansen 2000).

Observations

Remarks

Named for the "Greek callos, beautiful, and treis, three, referring to the beauty of the plants and the three-whorled leaves and cone scales" (Wunderlin 1993).

Birds feed on the seeds, and cypress pine jewel beetle larvae feed on the branches and trunks (Grodecki et al. 1996).

Citations

Adams, R. and D. Simmonds. 1987. A chemosystematic study of Callitris (Cupressaceae) in south-eastern Australia. Australia Forest Research 17(2):113-125.

Christiansen, D.L. 2000. Australian cypress. INTAD. http://www.intad.asn.au/materials/wd_cypss.asp (18-Jan-2002).
This site has quite a variety of information on commercial uses of Callitris wood, lists common names for many of the species, and has several links to photographs.

Garden, J. 1957. A revision of the genus Callitris. Vent. Contr. New South Wales Natl. Herb 2(5): 363-392.

Grodecki, Andy, Sylvia Willie and Matt Deshon. 1996. Queensland tree selector. Online database; these data cited at http://ocean.fit.qut.edu.au/tsm/html/treetext.html (18-Jan-2002).

Mehra, P.N. and T.N. Koshoo. 1956. J. Genet. 54: 181-185.

Wunderlin, Richard P. 1993. Cupressaceae. Flora of North America Editorial Committee (eds.): Flora of North America North of Mexico, Vol. 2. Oxford University Press.
This document is available online. Go to http://hua.huh.harvard.edu/cgi-bin/Flora/flora.pl?FLORA_ID=12395 and search for "Callitris".