Callitris columellaris

It is a small evergreen tree, 4–12 m (rarely to 20 m) high, with a trunk up to 50 cm diameter. The leaves are scale-like, 2–6 mm long and 0.5 mm broad, arranged in decussate whorls of three on very slender shoots 0.7–1 mm diameter. The cones are globose, 1–2 cm diameter, with six triangular scales, which open at maturity to release the seeds.

Some authors (e.g. Thompson & Johnson 1986, followed by the Flora of Australia Online) divide it into three species (or occasionally as varieties), based largely on the foliage colour, with green plants predominating on the east coast of Australia, and glaucous plants in the interior, and on cone size, with on average marginally smaller cones in tropical areas (north of 22°S). However, others (e.g. Blake 1959, Farjon 2005) point out that both the foliage colour and cone size is very variable, even from tree to tree in local populations, and maintain that it is impossible to distinguish three taxa within the species. When split into three species, the following names apply:

• Callitris columellaris F.Muell. sensu stricto – coastal northeast New South Wales, southeast Queensland.
• Callitris glaucophylla Joy Thomps. & L.A.S.Johnson (syn. C. columellaris var. campestris Silba; C. glauca nom. inval.; C. hugelii nom. inval.) – throughout most of the southern half of Australia.
• Callitris intratropica R.T.Baker & H.G.Smith (syn. C. columellaris var. intratropica Silba) – northern Queensland, northern Northern Territory, northern Western Australia.

Eric Rolls described the pollination of C.columellaris thus: "At pollination time when hundreds of cones go off together with a sharp crack and spurt brown pollen a metre into the air, the whole tree shivers."[7]

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  Mature tree, circa 1920
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  C. columellaris foliage
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  C. columellaris bark
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  Mature tree
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  Green fruit, Narrabri Shire
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  Mature fruit, Narrabri Shire

Wikispecies has information related to Callitris columellaris.

Wikimedia Commons has media related to Callitris columellaris.

• Blake, S. T. (1959). New or noteworthy plants, chiefly from Queensland. Proc. Roy. Soc. Queensland 70 (6): 33–46.
• Farjon, A. (2005). Monograph of Cupressaceae and Sciadopitys, pp. 507–513. Royal Botanic Gardens, Kew. ISBN 1-84246-068-4.
• Thompson, J. & Johnson, L. A. S. (1986). Callitris glaucophylla, Australia's 'White Cypress Pine' – a new name for an old species. Telopea 2 (6): 731–736.
• Conifer Specialist Group (1998). "Callitris columellaris". IUCN Red List of Threatened Species. 1998. Retrieved 4 August 2006.CS1 maint: ref=harv (link)old-form url
• "Callitris columellaris". Flora of Australia Online. Department of the Environment and Heritage, Australian Government.
• "Callitris glaucophylla". Flora of Australia Online. Department of the Environment and Heritage, Australian Government.
• "Callitris intratropica". Flora of Australia Online. Department of the Environment and Heritage, Australian Government.
• "Callitris glaucophylla". FloraBase. Western Australian Government Department of Parks and Wildlife.
• Gymnosperm Database - Callitris columellaris
• Gymnosperm Database - Callitris glaucophylla
• Gymnosperm Database - Callitris intratropica