Rules Target Killer of Oaks

Hoping to stem the spread of a deadly tree disease, federal officials today are expected to announce strict new quarantine rules that could affect the transport of bark chips, mulch and even Mother’s Day azaleas.

The U.S. Department of Agriculture is unveiling more stringent regulations governing nursery activities and the movement of nursery materials out of a 10-county area of coastal California.

The rules were designed to curb the spread of sudden oak death, a fungus that has killed thousands of oaks in northern and central areas of the state. The disease is believed to be related to the organism that devastated the Irish potato crop in the 19th century.

In California, the fungus has attacked tan oaks, black oaks and coastal oaks, and was found last month in commercial rhododendrons growing in Santa Cruz County near some stricken oak trees.

The new rules will take effect immediately. They will override existing state restrictions, which generally have been less restrictive on movement of such items as azaleas and bark chips, state officials said. Precise details, they said, will not be known until the rules are published today.

“The law states that if local regulations are more or less strict than federal regulations, the federal regulations proceed,” said Steve Lyle, director of public affairs at the California Department of Food and Agriculture.

But on at least one key point, the federal rules are expected to be less stringent.

The state focused on restricting the movement of plant materials from so-called “zones of infestation” to non-infested areas within the 10 counties. The federal rules may not regulate those zones, but instead may govern only what leaves the 10-county area.

USDA spokesman Larry Hawkins said Wednesday that he could not confirm that change or comment on specific aspects of the new rules until they are published.

“The USDA is trying to balance a lot of concerns with their rule,” added Bill Callison, assistant director for plant health and pest services for the state agriculture department.

The public will be able to comment on the interim federal rules at a Feb. 27 hearing in Petaluma.

Another public hearing will be held in Washington, D.C., and federal officials will then evaluate public comments and issue a final rule.