Smells may be used to 'tag' trees and track timber

New Zealand scientists have triggered research to tag felled trees with aromas, and use the smells to track the wood from the forest to its end use, whether as framing or furniture.

Robert Franich, of Scion, formerly New Zealand's Forest Research institute, and Glen Murphy, a forest engineering professor at Oregon State University, have developed a US$8000 ($11,700) prototype electronic "nose" that tracks the timber.

Prof Murphy tagged the wood with chemicals from the perfume industry, but his device has so far only been able to identify one scent at a time, the Seattle Times newspaper reported.

Five years from now, Prof Murphy hopes to be able to track 25 aromas in various combinations which would allow timber trackers to tag more than 33 million logs with a unique scent for each.

"Ideally, we want to track from standing tree to piece of wood on a desk," he said. "That's where we want to go. A smell is like a fingerprint."

Such a system could allow the timber industry to certify that individual products come from woods managed in an environmentally-sound way, or make it harder to move pirated logs, reducing theft and illegal logging.

Or they could help the industry improve its marketing and management. Some foresters currently use metal staples or plastic tags that risk problems with pulp mill and sawmill machinery, of radio frequency tags, which are expensive.

"One of the challenges the forestry industry faces is being able to track products through the supply chain," Prof Murphy said.

Some markets already used aroma tagging: food manufacturers relied on electronic noses to measure freshness, the medical and dental professions can use it to detect disease, and specific aromas released into a pipeline can help natural gas companies isolate leaks.

Each year 1.5 billion cubic metres of timber are harvested worldwide from up to 15 billion logs.

Prof Murphy said a truckload of about 50 logs can cost upward of US$2000, so timber manufacturers wanted to keep close tabs on their merchandise.

But to be effective, a wood sniffer system would have to be inexpensive and able to withstand harsh climates, difficult transportation conditions and treatments such as sawing, varnishing and staining.

Prof Murphy is looking for grant money from the US Department of Agriculture's Forest Service, the Oregon Department of Forestry and private timber companies.

- NZPA