State director Sam McQuestin said he had written to the Australian Electoral Commission requesting an investigation into an ad published in The Mercury yesterday.

British investigative journalist Clare Rewcastle, who runs the Sarawak Report website condemning the company's logging practices in Borneo, is believed to have placed the ad.

The ad headlined "Truth in Advertising" states "Ta Ann has accused the Greens of not telling the truth in advertising" and labels company ads promoting eco-wood as lies.

Mr McQuestin said the ad referred to the Greens' anti- forestry policies and campaign for greater scrutiny of the media.

Under the Commonwealth Electoral Act, electoral material must be authorised even outside an election period.

"It is typical hypocrisy from environmental groups to call for truth in advertising and to then not identify themselves, potentially in breach of the law," Mr McQuestin said.

"You can't hide behind anonymity to make statements that may be untrue or defamatory."

A similar ad published last month promoting a forum with Ms Rewcastle featured the same photo and was authorised by Tasmanian Greens Senator Bob Brown.

Yesterday, a spokeswoman for Senator Brown said he did not contribute to the latest ad.

On Tuesday, the Huon Valley Environment Centre released a report based on right to information documents showing the company had used wood from Tasmanian old-growth forests on 35 occasions.

"Ta Ann's operations here in Tasmania are far from eco- friendly and must rank among the worst logging practices globally," spokeswoman Jenny Weber said.

Neither Ms Rewcastle nor a Ta Ann spokesman could be contacted yesterday.