RIVERSIDE – The presence of the potentially devastating “citrus greening disease” was confirmed in a tree in east Riverside, prompting agricultural officials to implement a containment strategy to prevent the disease from spreading to crops throughout the area.
According to the Riverside County Office of the Agricultural Commissioner, tests performed Tuesday, July 25, on a grapefruit tree sample collected two weeks earlier from property near the intersection of Chicago and Marlborough avenues showed that huanglongbing – better known as citrus greening disease – had taken root.
The disease poses a threat to citrus crops in the Riverside metropolitan area and elsewhere, officials said.
The California Department of Food and Agriculture, in partnership with the U.S. Department of Agriculture, initiated a survey and treatment program to prevent the disease’s spread, which is enabled by the Asian citrus psyllid, a finger-tip size, moth-like pest that made its U.S. debut in Florida nearly 20 years ago.
“Crews will remove and dispose of the infected tree and are preparing to treat citrus trees within 800 feet for Asian citrus psyllid infestations,” according to a county statement. “Taking these steps will remove a critical reservoir of the disease and vectors that can spread the disease, an essential tactic in protecting nearby citrus.”
County Agricultural Commissioner Ruben Arroyo said both private and commercial grows are at risk.
“It’s important for residents, growers and agricultural officials to work together to quickly find this disease and stop its spread,” Arroyo said. “I encourage everyone to visit www.CaliforniaCitrusThreat.org to review symptoms of the disease and report disease sightings.”
There are more than 20,000 acres of commercial citrus crops in Riverside County, where oranges, lemons, grapefruit and tangerines are grown.
Psyllids originate in tropical and subtropical regions, including South America and south Asia. They first appeared in California in 2008 and have been trapped in citrus-growing areas throughout the Inland Empire, as well as Los Angeles, San Diego and Ventura counties.
Psyllids host virulent bacteria that can devastate plants’ vascular systems. The greening 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.
Arroyo said quarantine is already in place around the site of the infected tree.
“The quarantine prohibits the sale of all host nursery stock and the movement of all host plants and fruits within a five-mile radius of the find and applies to residents and commercial operations alike,” he said.
Different methods are used to combat psyllids. In 2011, the University of California Riverside Center for Invasive Species Research began releasing Tamarixia radiate – tiny stinger-less wasps – in the campus’s botanical gardens to keep psyllids out. The wasps lay eggs in psyllid nymphs, on which the wasp larvae feed, killing them.
Anyone with questions or concerns about huanglongbing and the threat posed by psyllids is encouraged to contact either the agricultural commissioner’s office at (951) 955-3045 or the state’s pest hotline at (800) 491-1899.