Waging War on a Green Invader : <i> Arundo donax</i> Is a Thirsty Monster That’s Choking the Santa Ana River

RIVERSIDE — Roy Felix adjusted his safety goggles, pulled on leather gloves and stepped into the dusty field to do battle. His foe was something out of a science-fiction novel--a 25-foot-tall green monster that grows several inches a day, seems indestructible and travels at breakneck speeds strangling everything in sight.

Meet Arundo donax , the killer weed of Southern California.

It is the major threat to the Santa Ana River, which supplies much of Orange County with water. Already in control of up to 10,000 riverbank acres, the weed is spreading environmental devastation, drinking enough liquid along the way to supply as many as 100,000 county residents a year.

“It’s like a cancer,” Felix’s boss, Paul Frandsen, said ruefully, watching the battle from a distance. “It must be stopped.”

Frandsen is the founding general of Team Arundo, a multi-agency hit squad that has become a model program by waging an aggressive war against the deadly plant, using chemicals and cutters from San Bernardino downriver to the coast. Team members include Orange County and the Orange County Water District, which earlier this year contributed $1 million to the cause.

“We haven’t found any organization known as Friends of the Arundo,” William Mills, the water district’s general manager, confided during a recent interview on the subject. “Every time somebody brings it up, I get excited. My blood pressure’s up right now.”

The plant wasn’t always public enemy No. 1. In the 18th Century in the Mediterranean region, where it grows naturally, builders used it as material. A bamboo-like cane with 1 1/2-inch stalks, the plant is perfect for providing stability to walls when embedded in adobe. So when the Spanish missionaries came to the New World in the 1700s, they brought the bamboo with them for use in constructing missions like the one at San Juan Capistrano.

For years it grew in isolated stands along the riverbanks. It wasn’t until the post-World War II development boom, however, that the cane began spreading downstream and forcing out native vegetation, a process that has accelerated in recent decades.

As a result, thousands of acres of land that 20 years ago lay covered by gentle cottonwood forests or open space is now literally clogged with thick wall-like patches of Arundo donax , an invasive plant that grows 4 to 5 inches a day, reaches a height of 25 feet and makes the area, in places, look like the jungles of Vietnam.

“It’s good for absolutely nothing; the only animals that can live in it are rats,” said Frandsen, assistant general manager of Riverside County’s Regional Park and Open-Space District.

Several environmental problems have ensued, he said.

The cane is highly flammable, causing regular blazes that cost millions to put out and destroying the natural vegetation further. Its roots clog up the river basin, catching sediment that builds up on the bottom, ultimately causing spills, changes in flow patterns and problems in flood control.

By destroying natural habitat, the Arundo donax has increased the already considerable risk to such endangered bird species as the least Bell’s vireo, southwestern willow flycatcher and warbling vireo. And in choking the banks of the river, the weed has blocked access to many spots once considered aesthetically pleasing recreational areas.

Most important, officials say, the Arundo donax is an extremely thirsty plant that drinks enough water to supply 50,000 to 100,000 people a year in north Orange County. At today’s prices, that water is worth $3 million to $6 million; by the year 2013, officials said, the water could be worth more than twice that amount.

“It’s a major nuisance in the watershed,” Mills said of the weed. “There is absolutely no benefit from Arundo , and if we don’t control it, it will continue to expand.”

Frandsen first began thinking about controlling the plant four years ago after arriving in Southern California from an assignment in Seattle. While the Arundo donax grows in virtually every riverbed in California, he learned, it is most pronounced along the 100 miles of Santa Ana River from San Bernardino County to Huntington Beach.

To fight the spread of the plant, Frandsen created Team Arundo, a group of nearly 20 local, county, state and federal agencies including Orange County and the Orange County Water District, the U.S. Fish and Wildlife Service, The Nature Conservancy, Caltrans, Santa Ana Watershed Project Authority and the California Department of Forestry and Fire Protection.

By appealing to the various member agencies, Frandsen said, he has been able to raise about $1.6 million--the bulk of it from the Orange County Water District--in the past three years. Another $600,000 is under negotiation. And over the next 20 years, which is about how long Frandsen thinks it will take to eradicate the weed from the entire Santa Ana riverbank, he hopes to raise $20 million more to finish the job.

Current efforts are focused at Hidden Valley, a 1,500-acre wildlife park on the outskirts of Riverside, where a handful of workers gathers seven days a week to poison and hack at the weed.

Felix, a groundskeeper for the Riverside County parks district who supervises the crews, takes the work in stride.

“It’s not hard work,” he said, “but you have to set a pace. The more you cut, the less it grows. Someday we’ll have it all done.”