Western Australia's biggest native timber processor, Auswest Timbers, is facing accusations it wasted thousands of tonnes of high-value jarrah sawlogs by selling them for low-value use in recent months.

Key points: A conservation group is angry that jarrah has been sold to make charcoal for producing silicon

A conservation group is angry that jarrah has been sold to make charcoal for producing silicon An industry group says it's unfair to label the use of wood in silicon production as low-value

An industry group says it's unfair to label the use of wood in silicon production as low-value Silicon producer Simcoa says the logs it purchased were degraded and were otherwise destined for firewood

Native forest conservation group WA Forest Alliance says the company sold as much as 10,000 tonnes of high-value jarrah from its timber mill near the south-west WA town of Greenbushes to make low-value charcoal used in the silicon production process.

WA Forest Alliance convenor Jess Beckerling said she was witness to the wastage.

"In early September, I stood here and saw the operation underway and you could see the marking from the Forest Products Commission (FPC) that show they're sawlogs being put through the mechanical log splitter," she said.

"We don't want to see any more of magnificent old forests being logged to produce more of these low-value products."

'Wasted' native logs

Simcoa confirmed it had bought 7,000 tonnes of degraded jarrah logs from Auswest Timbers. ( Supplied: WA Forest Alliance )

Ms Beckerling said she had also received reports Auswest Timbers had been on-selling whole logs to Bunbury-based silicon producer Simcoa and questioned if that constituted a breach of its supply contract with the State Government.

The FPC manages the logging of state-owned native forests and said it was aware Auswest Timbers had on-sold whole logs to other domestic processors but said that was not a breach of its supply contract.

The on-sale of whole logs to other domestic processors is because of a build-up of the company's timber stocks.

Matt Granger, acting CEO of the Forestry Industries Federation of WA, said he understood that technical issues with the processing facility at Greenbushes had led to a build-up.

"In terms of the re-tooling and disruption to their timber processing, it has been attributed to logs accruing on their log landing and timber will degrade if it's left too long," he said.

While it would have been preferable to use it for high-value processing, Mr Granger said it was unfair to label the use of wood in the production of silicon as low-value.

"It's actually producing a high-value added mineral product. It's employing lots of people and it's maybe being a bit precious to say that that is an inadequate market for this resource," he said.

Timber mill sale

Auswest Timbers has recently been sold to Parkside Group. ( Supplied: WA Forest Alliance )

The sale of timber happened while the processor was being sold by its parent company, Brickworks.

The processor was put up for sale because demand for native timber in WA had been flat and sale volumes had dropped, according to Brickworks' managing director, Lindsay Partridge.

The sale was announced to the ASX in March and the company said it would focus on realising the most value out of the remaining assets through an orderly exit process.

Simcoa confirmed it had bought about 7,000 tonnes of the timber miller's degraded jarrah logs.

Simcoa's general manager of production, Drew Harris, said Auswest Timbers approached the company some months ago, looking to create some value from a stockpile of old sawlogs.

"It's our understanding that the logs have been sitting in Auswest Timbers' yards for an extended period of time and have degraded to the point where, from its perspective, it was no longer economical to process them," Mr Harris said.

"If we weren't interested, they were going to process it into firewood. We saw better value in it coming to us."

Mr Harris said the company had a long-time policy to not to accept high-value jarrah logs.

In a statement provided to the ABC, Brickworks said, under its ownership, Auswest Timbers sold small volumes of sawlogs to other sawmillers when it did not have the capacity to process them.

"These logs were sold for the production of high-grade furniture and joinery products. None were sold for firewood."

Brickworks made no mention of the 7,000 tonnes of degraded sawlogs sold to Simcoa.

Auswest Timbers has recently been sold to Queensland-based company Parkside Group.