Hill says the four leading factors or “horsemen” which impact California’s citrus industry are markets, weather, California government regulations (estimated at $300 per acre), and diseases.

On the disease front, the California citrus industry is poised with both fists swinging at the ACP-HLB nemeses.

California Citrus Mutual and the Citrus Research Board developed a plan to form a statewide pest control district to attack the issue. California lawmakers crafted and passed Assembly Bill 281, a fast track effort signed into law to construct a statewide ACP-HLB plan.

Hill chairs the Citrus Pest and Disease Prevention Committee formed by the law. The body includes 14 growers, two citrus nurserymen, and one at-large member.

The group’s ongoing mission is to develop recommendations to the Secretary of the California Department of Agriculture (CDFA) on citrus pest and disease issues, an action protocol, educate and inform growers and the general public on the importance to survey and detect citrus vectors and diseases, and increase assessment dollars in the private sector to pay for programs, noting the huge shortfalls in the California State budget.

“It’s up to us (citrus industry) to pay for detection, mitigation and treatment,” Hill said. “To remain a citrus grower in this industry in the years to come we have to pay for this program.”

The committee recommended, and CDFA Secretary A.G. Kawamura approved, an assessment increase in October 2010 from 1-cent to 9-cents per 40-pound box of citrus. The increase will raise about $14 million annually to combat the threat.

“We will never eradicate the Asian citrus psyllid,” Hill stated. “As long as we keep it suppressed we should keep the insect contained.”

Most California ACP control efforts are concentrated on backyard citrus since, according to Batkin, backyards in Southern California likely have more citrus trees than the orchards in commercial production.

Treatment costs for backyard citrus are paid by the CDFA. The grower assessment fees are targeted for commercial citrus endeavors.

Backyard citrus

Given the large number of citrus trees in backyards in Southern California, the CRB has conducted numerous media interviews directed toward English and Spanish-speaking residents. CRB communications specialist Lynne Sanderson is delivering the ACP-HLB message at home and garden shows.

“We are at home and garden shows to meet key people in the community,” Sanderson said. “We are establishing relationships, getting addresses and lists, and working to follow-up with these people on additional ways to get out the message.”

Lawnmower shops, churches, and home owner associations are among the places and groups where the ACP-HLB message is playing.

Trapping

While CDFA is trapping for psyllids in urban settings, the CRB has about 7,500 traps across California’s commercial citrus belt, says the association’s field operations director Brian Taylor. Roughly one trap is placed on every 40 acres; about 16 traps per square mile.

Traps are placed on the outside perimeter of groves since that is where most psyllids are found. Adult ACPs primarily feed on the leaves and stems of citrus plants. Immature psyllids and eggs are found on the flush while adults are found year round. Nymphs excrete waxy tubules (honeydew) on the plant.

“It’s a small insect but it causes a lot of damage,” Taylor said.

The CRB electronically records trap information including the GPS coordinates, the tree health, and other information which is loaded into a database. Suspicious-looking plant samples are analyzed at the CRB laboratory in Riverside, Calif. using a polymerase chain reactive machine which checks the DNA.