SACRAMENTO, Calif. – California nursery owners have warned that the glassy-winged sharpshooter, a pest that can carry bacteria that causes diseases in ornamental plants and crops, poses an extreme financial threat to the state's industry, which represents California's third-largest agricultural crop. The impact of the pest’s infestation has caused shipments from some Southern California wholesale nurseries to stop completely. The potential economic damage impacts wholesale and retail nurseries and could ultimately affect landscapers, public groundskeepers, commercial gardeners and arborists who rely on nursery stock.
While the state has focused on protecting California's valuable winegrape industry, the economic impact on the state's nurseries is rapidly climbing into the millions. "The nursery industry feels a great urgency to find additional ways to contain this pest," said Gary Hayakawa, owner and president of Three Star Nursery in Fountain Valley, and board officer of the California Association of Nurserymen (CAN). "Every industry and governmental agency with a responsibility for containing this pest must begin to work in sync if we're going to be successful."
Declining shipments of nursery stock will have a direct consequence on jobs and sales tax revenue. Already, shipments from some Southern California wholesale nurseries have been curtailed due to concerns of transporting the glassy-winged sharpshooter and its egg masses to non-infested counties in Northern California.
Valley Crest Trees, a wholesale nursery in Ventura, has voluntarily halted all Northern California shipments, resulting in the loss of $3 million so far this year. Valley Crest Trees took this step due to its close proximity to infested citrus groves. If this trend continues, Northern California retail nurseries will find it difficult to replenish plant stock, causing sales to drop dramatically.
The nursery and landscaping industries produce the state's third-largest crop, providing $7 billion in annual revenues and employing 130,000 Californians.
Nurseries in infested counties are inspecting and spraying their stock prior to shipping to non-infested areas. The likelihood of sharpshooter infestation is greater when a nursery is located next to citrus groves as citrus groves are one of the pest's primary breeding grounds. Many in the industry believe that a key containment method would be to spray citrus groves to control sharpshooters, but currently there is no requirement that citrus growers comply with this need.
The glassy-winged sharpshooter first appeared in Southern California in 1990. It sometimes carries the bacteria that causes Pierce's disease in grapevines as well as other diseases in ornamental plants and crops. The sharpshooter is extremely mobile and, over the past decade, has made its way to areas as far north as Sonoma County. Highly adaptive, the pest can survive and lay its eggs on a variety of "host" materials that are not nursery stock.
Since 1997, CAN has contributed more than $100,000 for glassy-winged sharpshooter research. This year alone, it allocated $45,000 for research efforts and an additional $10,000 for development of an ovicide to attack the pest's egg masses. Most nurseries also voluntarily inspect stock before it is shipped and contact agricultural commissioners when crops are delivered from an infested county.
"We are calling on the state and County Agricultural Commissioners to ensure that all industries involved do their share to contain this pest," said Elaine Thompson, executive director of CAN. "Containment and eradication will not be realized until that happens."