The 'Australian Pine'

Overseas, it is called Australian pine - it bears a superficial resemblance to a pine tree (the conifer genus Pinus) because of its small, round, cone-like fruits and its branchlets that look like pine needles. It is never referred to as Australian pine in Australia.

It was introduced into Mexico before 1852, and the USA in about 1898.

There were anticipated to be a great many commercial applications of Australian pine. Its uses included as a hardwood, pulpwood (paper-making), and tannin, as well as the leaves serving as cattle fodder.

However, Australian pines have proven inadequate for every one of these applications.

As a source of food for cattle, it caused more problems than it solved - by interferring with the digestive system of the cattle. As a source of pulpwood, other long-fibered pulp (such as bamboo) must be added.

The timber is hard, heavy, and strong, with a fine texture and tightly interlocked grain - but the wood is too brittle - and prone to crack and split. It seasons unevenly - resulting in heavy and uneven shrinkage, severe cupping, surface checking, casehardening, and other defects. Sawing the wood is also difficult. (Saws tend to heat, chatter, and veer off course).

In countries where timber is scarce, the wood is used mainly for fenceposts and poles, beams, oars, mine props, rough barns, and other structures. Although regarded as durable in salt water, the wood is very susceptible to drywood termites and not long-lasting in the ground.

Due to its very fast growth rate, (1.5 to 3 metres per year), it is widely agreed that its number one use is as firewood - especially in third world countries where wood is scarce. It has a very high calorific value, and is therefore often dubbed "the best firewood in the world".

Because its roots are capable of producing nitrogen, Australian pine can colonise nutrient-poor soils. In China, a common practice is to plant it in infertile, previously overplanted fields. This gives the field much needed rest, restores fertility because of the plant's ability to fix atmospheric nitrogen, and provides a cash crop of highly saleable firewood when mature. Australian pine also has been found to have considerable potential for use in urban and industrial areas having air quality problems - due to its good sorption properties.

Many countries have established programs to reforest vast lengths of coastal dunes using Australia pine due to its resistance to salinity and desiccation. China has more than 1,000,000 hectares; India 800,000 hectares, and Vietnam 100,000 hectares, mainly in coastal areas where land degradation is worst (approximate 1996 figures).

Sawn Australian pine (source unknown).

Your online learning task:

This webpage describes a commonly occurring Australian hardwood that has been introduced into many countries world-wide and is now regarded as a weed or pest in some of them.

Given this information, answer the following questions: (i) the common name for this tree in Australia; (ii) the family to which it belongs; (iii) its uses in Australia - both now and in the past; (iv) a list of countries that now consider it a weed or pest; (v) find out what damage drywood termites can cause, what types of wood they attack, which type of drywood termite is the most destructive, and whether drywood termites are a problem in Queensland.

Use the World Wide Web (WWW) and/or your school library as information sources.

Web research:

Below, in the Glossary, are the meanings of some of the terms used in the background article.

To find your answers, select suitable keywords and search for them using your favourite search. If you do not have a favourite search, here are a couple of
search tools: Ask Jeeves for Kids; SuperSnooper.

If working online is new to you, SafeKids.Com is a website where both students and teachers will find tips, advice and suggestions to make your online experience fun and productive.

Extension tasks:

(i) how are the countries that consider Australian pine a pest ridding themselves of it?; (ii) find clear photographs on the WWW of the tree, the leaves, and the small cones; (iii) when referring to timber, find the meanings of the terms shrinkage, cupping, surface checking and casehardening; (iv) research at least one other timber defect in detail - explaining what negative consequences it has on the timber's properties; (v) what other Australian trees grow very quickly - at up to 3 metres per year - like the Australian pine?

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Glossary

branchlet: A small branch or the terminal or ultimate subdivision of a branch.

desiccation: dryness resulting from the removal of water.

exotic: From another part of the world; foreign; not native.

fodder: livestock feed.

heartwood: the hard wood at the core of a tree trunk.

keyword: A word used as a reference point for finding other words or information.

native: An animal or a plant that originated in a particular place or region.

naturalise: To adapt or acclimatise (a plant or an animal) to a new environment; introduce and establish as if native.

plantation: A large group of cultivated trees or plants.

salinity: higher than normal levels of chemical salts in the soil.

sapwood: In a woody plant, the softer part of the wood between the inner bark and the heartwood, and is usually lighter in color and more active in water conduction than the heartwood.

superficial: only what is apparent, shallow; concerned with and understanding only the obvious.

tannin: tannic acid.

thicket: A dense growth of shrubs or underbrush.

Copyright D. L. Christiansen [Last updated February 2001] Images: respective copyright owners noted/cited.

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