GRANTS PASS, Ore. -- A woman who turned herself in after a decade as a fugitive in the largest-ever U.S. ecoterrorism investigation pleaded not guilty Friday to conspiracy and arson charges in federal court.

With Canadian citizen Rebecca Rubin, 39, sitting shackled in the jury box, Magistrate Judge Thomas Coffin ordered her to remain in custody and set trial to begin March 19 in U.S. District Court in Eugene, said Assistant U.S. Attorney Steven Peifer.

A federal indictment accuses Rubin of being a member of cells of the Earth Liberation Front and Animal Liberation Front known as The Family. Investigators blame the group based in Eugene for 20 fires across the West from 1996 to 2001 that did $40 million damage.

She turned herself in to the FBI last November at the Canadian border with Washington state. At the time, her lawyer said she wanted to get the case behind her.

Defence lawyer Richard Troberman, of Seattle, did not respond to an email seeking comment Friday.

Investigators blame the cells for fires at a ski resort in Colorado, wild horse corrals in Oregon and Northern California, and lumber mills and U.S. Forest Service offices in Oregon.

Ten people pleaded guilty in 2007 to conspiracy and arson charges and were sentenced to prison. Two others indicted in the case remain at large.

Rubin is specifically charged with helping set fire to buildings at the Vail ski resort to prevent expansion into habitat for the threatened Canada lynx, and to U.S. Bureau of Land Management corrals in Eastern Oregon and Northern California holding wild horses rounded up from federal rangelands.

She also is accused of trying to set fire to a lumber mill office in Medford, Oregon.

Rubin is not specifically charged with terrorism, but the indictment alleges she and other members of The Family tried to influence businesses and the government and tried to retaliate against the government.

At the time of the fires, the FBI characterized the Earth Liberation Front and the Animal Liberation Front as the top domestic terrorism threats in the nation.

The Family disbanded in 2001, but a federal task force known as Operation Backfire used an informant to pursue them.

By the time they were sentenced, members of The Family expressed regret and frustration that after all their hardships, they had accomplished practically nothing.

A horse slaughterhouse in Oregon was never rebuilt, but the ski resort and ranger stations were rebuilt, timber companies stayed in business, and wild horses were still rounded up and removed from federal lands.