Australian Cypress

Australian Cypress (sometimes referred to as 'White Cypress' or, incorrectly, as 'Cypress pine') belongs to the genus Callitris, of which there are about 16 species. 14 are native to Australia, the other two to New Caledonia (a south Pacific Island). Australian Cypress is also naturalised in Florida, USA. Australian Cypress has a similar appearance to trees of the Pinus species [2].

Of the Australian species, eleven have been used for their timber and are referred to by the common name "Cypress" [14].

The largest species is Stringybark (Callitris macleayana) - also commonly known as Brush Cypress and Port Macquarie Cypress. It is mostly found in rainforest, on the coast north from Port Stephens, NSW to north Queensland (Atherton). This species grows to 50 metres [2].

Historically, Aboriginals have used the bark, timber and oils for various purposes (wood: oars, spears; resin: glue/cement; bark: natural medicine) [15].

Currently, tannin, resin, and fragrant oils are extracted from the trees [1].

Australian Cypress (Callitris glaucophylla) is, commercially, the most important species [3].

Australian Cypress is a small to medium-sized tree, usually growing to about 18 metres tall, but occasionally reaching 30 metres, and has a straight trunk [1].

Small quantities of Black Cypress (Callitris endlicheri) are also logged [3]. This species is usually smaller and more erect than the more commonly occurring Australian Cypress.

Distribution in Australia

Australian Cypress is widely distributed in inland areas of Australia with moderate rainfall - growing primarily in southern Queensland and northern New South Wales. Today it forms extensive forests only in the Tambo-Dalby-Inglewood region of southern Queensland and the Baradine-Narrabri and Cobar districts of northern New South Wales [1]. Commercial quantities of the timber mostly come from state forests [3].

All of these forests are contained in the Murray-Darling Basin. The periodic flooding in the basin is critical due to the moderate rainfall of 300 to 650 mm a year and the region's climate. The Pilliga State Forest, located north of Coonabarabran NSW, is the only large area in the Murray-Darling Basin that has naturally regenerated from sparse open woodland to forest over the period of European settlement. This is essentially due to the elimination of Aboriginal burning and livestock grazing. By the early 1900s, the elimination of burning was resulting in very dense growths of Australian Cypress - and is now the largest expanse of inland plains forest in Australia. The Pilliga is approximately 430,000 hectares of which Australian Cypress covers about 80% [6].

These extensive natural remaining forests are managed by their respective state forestry departments to maximise the economic returns. There are no successful Australian Cypress plantations that have been established in Australia (like the plantations established for exotic pine species such as Radiata pine). Cypress is considered to be unsuitable as a plantation species, due to its tendency to "lock-up", that is, for each Cypress tree to put out an exudate through its roots and leaves which inhibits the growth and dominance of its neighbours, thus stalling the overall growth of the whole population. [3]. As the Pilliga example above demonstrates, Cypress is not a natural monoculture tree - it grows best in open woodlands with Eucalyptus and other species [7].

Queensland Forestry thins the stands of Australian Cypress to about 300 trees per hectare (1 ha = 2.5 acres). Non-commercial species that are crowding or overtopping the cypress are also removed. The growth rate is claimed to increase by up to ten times as a result of this treatment [17].

In Queensland, in 1999, the Australian Cypress industry generated $30 million per year and employed more than 2,000 people directly and indirectly. It is one of the most decentralised timber industries in the world. Australian Cypress mills operate in Inglewood, Millmerran, Cecil Plains, Chinchilla, Miles, Taroom, Wandoan, Injune, Roma, Augathella, Mungalla, Dulacca and Surat. Mitchell and Tambo may also soon have mills [16].

More than 130,000 cubic metres were logged in Queensland in the 1996/97 financial year.

In the Northern Territory, in the mid 1960's to early 1970's, Northern Cypress (Callitris intratropica) forests were also planted and managed - until poor growth rates led to Pinus caribæa (see the page on Pines in Queensland) becoming the preferred plantation species in the Territory. The National Forest Inventory (1997) shows no Callitris forests in the Northern Territory (of over 1000 hectares) [8]. In Queensland, wood from northern Queensland grown Northern Cypress is transported to southern Queensland for oil extraction [9]. The oil distilled from this species has a cobalt blue colour.

Properties

Callitris wood is often attractively marked, and for a softwood, is fairly hard and dense. Hoop pine has a seasoned hardness rating of 3.4 kN, Radiata pine 3.3 kN, and Cypress 6.1 kN. Cypress has a seasoned density of approximately 700 kg/cu.m, compared to the other two at 550 kg/cu.m [4]. It therefore has earned the title of the world's hardest coniferous timber.

Australian Cypress has high resistance to termite attack in ground contact or in damp or poorly ventilated situations. Both sapwood and heartwood are resistant to preservative impregnation [4].

The sapwood is resistant to Lyctus borer attack. High resistance to marine organisms is also reported [1].

Therefore, unlike CCA pine and many hardwoods, Australian Cypress requires no treatment. The presence of natural substances in the wood (resin, guajol and callitrol) give the timber its resistance. This makes it potentially safer than other timber species for use with children. (Callitrol is a phenolic compound that imparts a camphor-like odour to the wood).

Caution: Other species of Callitris (eg, Black Cypress) do not display the same resistance - so exercise care if you are purchasing Cypress for its resistance properties.

The timber is fairly easy to work although there is some tearing of grain around knots. It dresses well to a smooth finish and takes a high polish. There is some tendency to split when nailed - so pre-drilling is recommended [1].

It demonstrates high dimensional stability (the dimensions remain stable - it does not expand and shrink very much) after it is seasoned.

Uses

This is a durable softwood timber often seen as flooring, decking and weatherboards in old houses, furniture components, posts and small poles [3]. (For photographic examples of each of these uses, see the link to Terry J. Newman P/L, below).

Other Queensland species

Another common Cypress (Callitris columellaris) is called the 'Coast Cypress', 'Bribie Island pine' or 'Cooloola Cypress'. This variety prefers deep sandy loams and occurs on the coastal strip from Richmond River, northern NSW to Hervey Bay, Queensland [2].

The meaning of 'callitris'

Greek callos, beautiful, and treis, three, referring to the beauty of the plants and the three-whorled leaves and cone scales.

Common & Botanical names used for Australian Cypress

Of all of the commercially significant Australian species of timber, there is more confusion over the correct common and botanical names for Australian Cypress ('white cypress') than any other woody plant genus.

As Callitris is a genus of the cypress family (Cupressaceae) - and not part of the Pinus genus of the pine family (Pinaceae) - the name 'pine' should not be used when referring to these trees. The preferred name is Australian Cypress (rather than the general name "white cypress" - which, as stated above, can refer to as many as 10 other species of Callitris).

Note: The rest of this section on common and botanical names is probably only useful if you are going to look for more information on Australian Cypress.

Some references claim up to 19 Callitris species - mainly due to whether the term "species" is used, or the tree is classified as a "variety" of another species.

The Australian National Botanical Gardens "Australian plant common name database" returns the botanical name "Callitris hugelii syn. Callitris glaucophylla" for Australian Cypress [11]. This means that the scientific name was Callitris glaucophylla, but has been changed to Callitris hugelii.

Other references refer to the botanical name Callitris glaucophylla as synonymous with Callitris columellaris var. campestris. [2].

There are references that treat Callitris glaucophylla, Callitris columellaris, and even Callitris intratropica, as varieties of the same species. [2], [11], [7]. "Several previously known species have now all been grouped under the one name of Callitris columellaris. This is a particularly widespread species and is found in all mainland states. In South Australia it is prevalent in the scenic Flinders Ranges where it is sometimes the dominant tree on rocky slopes and rises" [18]. Some references state that the botanical names Callitris glauca and Callitris hugelii have been applied erroneously to it. [2].

Be aware of this if you require more information on Australian Cypress.

Lastly, in the USA - where Callitris glaucophylla is an exotic species - it is commonly known as "cypress pine" or, sometimes, "blue cypress".

Therefore, when searching for information on Callitris, any of these botanical and common names will provide information. (i.e. It may be best not to limit your search to just Callitris glaucophylla).

More Online Information

For great photographs of Australian Cypress applications, follow this link to Terry J. Newman P/L (Two pages of "wood in use" photos: flooring, decking, panneling, framing, fencing, LOG HOUSE) [12].

For detailed Australian Cypress TECHNICAL DATA, follow this link to Terry J. Newman P/L's website. (at the bottom of this webpage is a link to technical information, also) [12].

For the Timber Research Unit, School of Architecture, University of Tasmania's datasheet detailing properties of Australian Cypress, follow this link [4].

For a photo and description of Australian Cypress from State Forests of NSW, follow this link. The distinctive resinous smell of the timber is described here as being similar to the smell of a surfboard [10].

For a photo of Black Cypress follow this link to the Australian National Botanic Gardens website [5].

For a photo of Black Cypress leaves and cone, follow this link to the Australian National Botanic Gardens website [5].

Follow this link to see the Queensland DNR Fact Sheet on Australian Cypress [13].

Next >> Soil Salinity & Pine!

Citations

[1] Agriculture Western Australia (1998, December). Timber Advisory Notes ["Number 39: Cypress Pine"] [WWW Document] URL http://www.agric.wa.gov.au/programs/srd/farmforestry/TAN39.HTM (visited January, 2001).

[2] Earle C.J. (Editor) (1999, March). Gymnosperm Database: Taxon Descriptions ["Araucariaceae"] [WWW online database] URL www.conifers.org/

[3] Rainforest Information Centre (RIC) (1999, December) RIC Good Wood Guide ["Australian Native Timbers"] [WWW Document] URL http://forests.org/ric/good_wood/ (visited January, 2001).

[4] School of Architecture, University of Tasmania (Australia) (2000). Species Detail [WWW Online database] URL http://oak.arch.utas.edu.au/tech/species.html

[5] Australian National Botanic Gardens (undated). ANBG: Photographic Images [WWW Document] URL http://www.anbg.gov.au/images/photo_cd/ (visited January, 2001).

[6] Murray-Darling Basin Initiative (undated). Forestry [WWW Document] URL http://www.mdbc.gov.au/education/Encyclopedia/Forestry/Forestry.htm (visited January, 2001).

[7] NFI (National Forest Inventory) (1998). National Forest Inventory Australia: Callitris Forest [WWW Document] URL http://www.brs.gov.au/nfi/forestinfo/callitris.html (visited January, 2001).

[8] NFI (National Forest Inventory) (1998). National Forest Inventory Australia: Tenure of callitris forests by State and Territory [WWW Document] URL http://www.brs.gov.au/nfi/forestinfo/table20.html (visited January, 2001).

[9] ANU Forestry Department (1998, October). Australian National University - Forestry: Essential Oils - an Overview [WWW Document] URL http://www.anu.edu.au/Forestry/wood/nwfp/essoil/EssOil.html (visited January, 2001).

[10] NSW State Forests (undated). State Forests of NSW: Quick Trips ["White Cypress"] [WWW Document] URL http://www.forest.nsw.gov.au/sfkids/adventures/woodwork/12_wood.htm (visited January, 2001). ["Quick Trip takes you on a shortcut through NSW State Forests"].

[11] Australian National Botanic Gardens (undated). ANBG: Australian plant common name database [WWW Online Database] URL http://www.anbg.gov.au/common.names/common.f.html (visited January, 2001).

[12] Terry J. Newman (undated).Terry J Newman Pty Limited (Australian Cypress exporters). Canberra, Australia [WWW Document] URL http://www.tjn.com.au/cypress_eng/index.htm (visited January, 2001).

[13] Queensland (Australia) Department of Natural Resources (2000, February). DNR Forest Facts: Australian Cypress [Portable document format] URL http://www.dnr.qld.gov.au/resourcenet/fact_sheets/pdf/forest/F07.pdf

[14] Robson, P. (Victorian Woodworkers Association) (1995) TREES OF AUSTRALIA: Index of Common Names [WWW Online Database] URL http://home.vicnet.net.au/~woodlink/toa.htm (visited January, 2001).

[15] Australian National Botanic Gardens (2000). Aboriginal Trail [WWW Document] URL http://www.anbg.gov.au/anbg/aboriginal-trail.html (visited January, 2001)

[16] Queensland Parliament (1999, July). Queensland Parliament Hansard Documents: July 1999 [Portable document format] URL http://www.parliament.qld.gov.au/handocs/1999.pdf/990721ha.pdf (visited January, 2001)

[17] Taylor, T. (for Department of Primary Industries Forest Service, Brisbane) (1994). Growing Up: Forestry in Queensland. Australia: Allen & Unwin.

[18] Holliday, I & Hill, R. (1974). A Field Guide to Australian Trees. Australia: Rigby.

Copyright D. L. Christiansen [Last updated October 2001] Images: respective copyright owners noted/cited. My thanks to Mr Terry J. Newman for his advice about Australian Cypress. His help has been invaluable [12].

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