Tiny citrus critter requires big-time pest control

Facing dreaded citrus psyllid, small Valley nurseries also threatened by protection costs.

Published online on Monday, Oct. 19, 2009

The much-feared Asian citrus psyllid hasn't been found in a San Joaquin Valley grove yet, but it may already be taking its toll on some citrus nurseries.

Over the past six months, several of the state's larger nursery owners have spent hundreds of thousands of dollars building screen houses to protect their valuable young trees against the psyllid, an aphid-sized bug capable of carrying a tree-killing disease known as citrus greening.

Smaller nurseries could be forced to do the same -- and many won't be able to afford it, industry observers agree.

The state has mounted an all-out effort against the bug, which has been found by the thousands in Southern California. Although the screen houses are not required, many believe it's just a matter of time.

"If anyone in the nursery business is surprised that this is happening, they have not been paying attention," said Roger Smith, general manager of TreeSource Citrus Nursery in Exeter. "We have been preparing for this."

But Ivanhoe citrus nursery owner Jerry Hobbs fears that the push to protect the state's $1.3 billon citrus industry may force him out.

Citrus experts say the cost of building protective buildings ranges from $300,000 to more than $1 million, depending on the size of the operation. That's too much for Hobbs' 47-year-old company to bear.

"That will put me out of business," Hobbs said. "And I just don't see how any smaller nursery will be able to make it."

The effort to shield young trees is focused on nurseries because that is the source of replacement trees for the entire industry. If trees in nurseries are infected, the disease easily could spread far and wide.

Industry officials acknowledge that there will be casualties in their fight against the psyllid. They saw it in Florida, where smaller nurseries could not afford the cost of screen houses.

In California, there are about 35 commercial citrus nurseries, and officials estimate that about 10% are smaller operators and could close.

"Unfortunately, this will be one of the costs of doing business. It is a reality," said Ted Batkin, president of the California Citrus Research Board in Visalia. "But the risks for not protecting the trees is too great."

Batkin and other citrus researchers say they've learned much from Florida's experience with the psyllid and the devastation it caused there.

Citrus greening, also known as Huanglongbing, has killed tens of thousands of acres of citrus in Florida since being discovered in 2005. The disease also has spread through Asia, Africa, the Arabian Peninsula and Brazil.

In Florida, Batkin said, state agricultural officials mandated protective structures for citrus nurseries as a way to keep the bug and the disease from spreading.

That scenario could happen in California.

"If it is not done by the Legislature, it will be done by the [California Department of Food and Agriculture]," Batkin said.

CDFA spokesman Jay Van Rein acknowledged that such actions are possible. But any mandatory plan to screen nursery stock would happen in partnership with county and federal agricultural officials.

"This would be as part of a larger effort and would not happen arbitrarily," Van Rein said.

Already, quarantines restricting the movement of citrus and plant material have been established in all of Los Angeles and Orange counties and portions of San Diego, Imperial and Riverside counties.

County agriculture department dog teams in Fresno and Sacramento have discovered psyllids in packages at FedEx facilities. So far, no other psyllids have been found in either city.