RIVER ARUNDO TOPS ON CITY'S MUST-GO LIST.

Byline: JUDY O'ROURKE

Staff Writer

SANTA CLARITA -- Aided by a recent grant, the city will soon resume its ongoing battle against an invasive nonnative plant that fuels spreading wildfires and sucks the soil dry.

Santa Clarita's effort is part of a regionwide push to cleanse the Santa Clara River of the bamboo-like arundo donax, which grows up to 25 feet high and chokes out beneficial native species.

"Two years ago, you couldn't see across the river -- you couldn't see the other bank," said Heather Merenda, the city's sustainability planner, recalling arundo's status before conservation crews waged a successful attack on the invader in 2005. "This thing comes back in spades every year if you don't remove it properly and maintain the removal."

Eradication efforts stalled in 2006 when funds dried up. But progress has been made eliminating the reedy grass from 297 city-owned acres of the river.

Encouraged by the gradual return of native plants and animals where arundo once spread jungle-like, the city plans to redouble its efforts and will prevail on property owners to join in the fight.

Just last month, the Los Angeles Regional Water Quality Control Board provided a $129,000 grant to help fund arundo removal and create a demonstration site offering step-by-step removal tips for homeowners.

Water conservation is key for the agency, which has partnered with many cities in its jurisdiction that have targeted the invasive plant.

"The arundo just sucks up all the water and we are very happy to be involved in removing it," said Francine Diamond, chairwoman of the agency board.

The reedy Eurasian grass has proven tough to thwart because its hardy roots -- which can reach 3 feet below the ground -- quickly regrow. When the plant goes to seed, the plant is cut at its base and the stalks are chipped and used as mulch, but the root is left intact.

Two years ago, the water-safe herbicide glyphostate was gingerly applied under the supervision of a biologist. The chemical is absorbed into the roots.

Arundo was not always seen as an enemy. It gained in popularity after being introduced into California landscapes a century ago, but its fast-growing riverbed invasion has proven anything but pretty.

The plant absorbs up to four times more water than willows and crowds out native species. Thickets of arundo can block storm runoff, which often results in flooding. During summer, the towering stalks become paper-dry, creating a fire hazard -- and in 2003, they were wicks in a fast-moving blaze.

"The Val Verde fire spread across the Santa Clara River because sparks landed on the arundo and allowed it to spread," Merenda said. "It went up the hills into Simi Valley and ended up in Stevenson Ranch."

The U.S. Forest Service has been attacking the plant since 1995, and says it has been successful in eliminating it from San Francisquito Creek, a branch of the Santa Clara.

"It's not something you can remove with one treatment. It takes follow-up -- we've been treating year to year because it re-sprouts," said Teresa Sue, a district biologist for the Forest Service. "Our success is based on going back and doing follow-up treatment."

Other regional agencies, including the Ventura County Resource Conservation District and the Natural Resources Conservation Service in Lancaster, are working with Santa Clarita to solve the problem.

The plan is to start from the uppermost reach of the river in Acton and work downstream toward the mouth of the river in Ventura.

"If we don't start at the top and work with private property owners, during the next storm a flotilla of arundo will flow down the river, and when waters recede, the plants will start growing there again," Merenda said.

Other river-bound plants on the city's hit list are tamarisk, castor bean, yellow starthistle and tree tobacco.

The city plans to resume its eradication plans in July.

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