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Forestry, wood processing & certification

Like to know what wood to use building a pergola or framing a barn? How about the difference between tung oil and polyurethane as a floor finish? How to revive decking or deal with merbau stains? Or how to meet the building code or bushfire standards? Or ask about the environmental advantages of wood or forest certification?

Q. I'm looking for FSC certified timber to be used to frame a verandah (Sydney, west facing), to be painted. The post size is 145x145 and the beam size is 250x45 - (more for aesthetic reasons than structural). I'm looking for something that has minimal shrinkage, a low tendency for twisting and warping, and with good durability. Thanks very much!

In the relatively large sizes you quote, the only sources of suitable timber would be (a) glue laminated or (b) recycled. Glue laminated timber can be supplied in a naturally durable species, or preservative treated pine. We suggest you contact Managed Timbers Australia who claim to have access to FSC-certified softwoods and hardwoods. Their phone number is (02) 9652 1321. In Australia, timber certified under the Australian Forestry Standard is more readily available, and in our opinion equally environmentally sound, so you might consider including this in your search. Suppliers of recycled timber can be found on the net by writing "recycled timber Sydney" into your browser.

Q. Is a plantation of trees specifically earmarked for an end use (e.g. woodchips, sawn, or veneer)? Or are high quality trees from the plantation directed to making veneer and lower quality trees sawn into boards or processed into woodchips?

In some parts of the world plantation pine is "high pruned". By removing the lower branches, knot-free timber is produced. This can be turned into clear timber for mouldings, or used for veneer. More commonly plantations are less intensively managed, and logs are selected according to quality. If a plywood factory is nearby, or integrated into the company's production, the best logs will go to making veneers. The veneers may be turned into plywood or used to make laminated veneer lumber (LVL). Other logs may be sawn for structural timber, as used in house framing, or appearance-grade material such as flooring. Woodchips are generally produced from "thinnings" and waste. "Thinnings" are the less favourable logs removed from the forest at intervals to allow the better formed trees to grow to maturity.

Q. What products are usually made from softwoods and what products are made from hardwoods? Has there been a trend over the last 10 years of softwood replacing hardwood products? What percentage of softwood timber is exported (v. used in Australia)?

Broadly, the trend over the last few decades has been for hardwood to move into areas where its appearance qualities (eg. in flooring, furniture, etc.) and its higher strength (eg. in kiln-dried structural products) can command a higher price. Consequently, there is relatively little unseasoned hardwood house framing used these days, and other low value hardwood products have declined, with their place taken by plantation pine. Pine is a versatile timber which now dominates the house framing market and can be readily preservative treated for outdoor use. With regard to statistics on hardwood v softwood production, and imports v exports, we rely on the report Australian forest and wood products statistics, published at intervals by the Australian Bureau of Agricultural and Resource Economics (ABARE). The latest issue covers the September and December quarters of 2009 and was published on 25 May, 2010. It can be downloaded from www.abare.gov.au. Go to ABARE data and click on "Forestry" in the drop-down menu.

Q. What is timber? How do we produce timber from a tree?

Wikipedia gives this definition of timber: In the United Kingdom and Australia, "timber" is a term used for sawn wood products (that is, boards), whereas generally in the United States and Canada, the product of timber cut into boards is referred to as lumber. In the United States and Canada, "timber" often refers to the wood contents of standing, live trees that can be used for lumber or fibre production, although it can also be used to describe sawn lumber whose smallest dimension is not less than 5 inches (127 mm). Timber is produced by passing a log through a saw, either a circular saw or more commonly a bandsaw.

Q. I entered a previous question about Australian wormy chestnut. My information says that it is predominantly Eucalyptus obliqua, Eucalyptus sieberi and Eucalyptus fastigata. Is there any possibility that these are from old growth forests in East Gippsland?

Thank you for this further information. The three species you mention are more commonly referred to as messmate, silvertop ash and brown barrel, but no doubt it is simpler to group them under one name for marketing purposes. We cannot say from which precise area your timber will be harvested, but we can say that the East Gippsland forests are administered under a management plan that conserves representative areas of old-growth forest. You can find the East Gippsland Forest Management Plan on the Victorian Government's Department of Sustainability & Environment website at www.dse.vic.gov.au.

Q. I understand that Austrailan Wormy Chestnut is given its detail through the natural wear on the trees such as drought and fire . This leads me to think that the wood is old-growth. Please give me more info about the sourcing of this wood in SE Australia.

Strictly speaking there is no such thing as Australian wormy chestnut, although it is advertised widely in the US. However, it is not a recognised standard common name for any Australian species. Chestnut (Castanea spp) does not occur naturally in Australia. It would appear to be a marketing name applied to an Australian species more usually known by other names. If you can find out the botanical name or standard common name of the timber in question we will attempt to advise you further.

Q. I am soon to build a home and want to make it as environmentally friendly as possible. I'd like to know the best source for sustainable pine framing, from certified forests please, thanks!

Whether timber is produced "sustainably" or not is tested by assessing production against a range of criteria and indicators set out in standard documents, such as the Australian Forestry Standard (AFS). The assessment process is carried out by independent organisations which can then certify that the products come from properly managed forests. The great majority of Australian growers of plantation pine have achieved certification to the AFS, while a number of growers are also certified against the Principles and Criteria of the Forest Stewardship Council (FSC). Major Australian hardwood producers are also certified under these systems. You can find out more about the Australian Forestry Standard and download copies of a newsletter and fact sheets from the net at www.forestrystandard.org.au.

Q. How old can the trees grow until they die?

The life span of trees varies greatly depending on the species. It can be as short as 35 years for apple trees, or as long as several thousand years, assuming an adequate water supply is maintained. You can find a chart on the net that gives the expected life span of a range of tree species. Click on this link for details: http://www.cnr.vt.edu/4h/BIGTREE/TreeAge.htm.

Q. How can I be sure the wood that I buy is not illegally logged?

The Australian Government is working with the timber industry to eliminate trade in illegally sourced forest products. The Government’s policy document, Bringing Down the Axe on Illegal Logging, was released in October, 2007.

A key element in this policy is the promotion of certification and chain-of-custody schemes. For more information, have a look at some of the publications on the Forestry and Wood Products Australia website (www.fwpa.com.au). You can find them by typing the words “certification” and/or “chain of custody” into the site’s search function.

Q. If we use more wood for building, won't we run out of trees?

Australia’s timber is sourced from a combination of sustainably managed native forests and plantations. We can’t significantly increase the use of our native forests, since they are not expanding, and we cannot harvest timber any faster than it grows. However, we can expand our plantations.

Much more timber is produced in a plantation than in the same area of native forest, and although the increase in softwood plantations has slowed in recent times, there will be a gradual increase over the next 20 years.

WoodSolutions

Did you know?

Logs from plantations cannot produce the sawn hardwood timber produced from logs currently harvested from native forests.