County to continue enforcing quarantine to prevent spread of citrus disease


The Riverside County Board of Supervisors signed off Tuesday, June 11, on a new contract with the state for ongoing use of Riverside County Office of Agriculture staff to handle the enforcement of regulations intended to contain and eliminate citrus greening disease.

In a 5-0 vote without comment, the board authorized county Agricultural Commissioner Ruben Arroyo to complete a yearlong $518,396 contract with the California Department of Food and Agriculture.

The most recent compact will terminate June 30, and the new one begins July 1.

Funds will be allocated for on-site inspections, confiscations, documentations and other measures needed to identify and mitigate threats and risks posed by the Asian citrus psyllid.

According to the U.S. Department of Agriculture, psyllid infestations have been uncovered in numerous locations in northwest and southwest Riverside County.

In July 2017, a grapefruit tree and two other trees in the area of Chicago and Marlborough avenues in Riverside became infested with the pests, prompting the state to place a quarantine over a 94-square mile area encompassing both Riverside and San Bernardino counties.

Under the still-active state order, only citrus products that are “commercially cleaned and packed” are permitted to be shipped out of the quarantine zone.

No citrus nursery stock can be moved outside the area under quarantine, and no residentially grown citrus fruit can be moved. However, growers may continue to consume and share with people within the quarantined locations. A map of the impacted area, along with the boundaries of similar quarantines in Los Angeles and Orange counties, can be found at

In August 2017, the board declared a local state of emergency because of the potential spread of huanglongbing, better known as citrus greening disease.

The county’s roughly 20,000 acres of commercial citrus crops yield about $187 million annually, and greening disease poses a direct threat, according to agricultural officials.

The city of Riverside’s foundational citrus-bearing tree, known as the “parent navel orange tree,” located at the intersection of Arlington and Magnolia avenues, received protective netting and treatment in April to prevent an Asian citrus psyllid infestation.

The tree is listed as a California Historic Landmark and has been preserved since 1873.

Psyllids host virulent bacteria that cause greening disease, which destroys plants’ vascular systems. The finger-tip size, moth-like insects made their U.S. debut 20 years ago.

The disease rampaged throughout Florida in 2005 and has inflicted an estimated $3 billion damage to crops in the Sunshine State, according to a study published by the University of Florida.

Psyllids originate in tropical and subtropical regions. They first appeared in California in 2008 and have been trapped in citrus-growing areas throughout the Inland Empire.