A county report urges control of vineyard pests in Temecula Wine Country

Population counts for the insect blamed for spreading the vine-killing Pierce's disease are at levels not seen since a Pierce's epidemic ravaged Temecula Wine Country vineyards in 2000, according to a county report.

The report by the Riverside County Agricultural Commissioner's Office doesn't predict a new epidemic, but urges growers to do their part to control the glassy-winged sharpshooter.

"There is no room for ambivalence or complacency in this ongoing battle," read the report, which was to be filed with the county Board of Supervisors today

If the population is not kept in check, "the pastoral beauty, elegance and distinction of this unique region of the county will be at risk," the report read.

The Pierce's outbreak of a decade ago killed a third of Wine Country vineyards and caused an estimated $20 million in damage.

Sharpshooters spread the disease as they roam from vine to vine. The untreatable, bacterial disease cuts off vines' water supply.

Special pesticides applied to grape vines can repel or kill the sharpshooter while not harming humans.

Most vineyards take the proper pest-control steps, according to the report. But the failure of some growers and farm managers to do so is "one very frustrating factor" in the sharpshooter population growth, the report found.

Warm winter weather, increased urbanization and a growth of host material in waterside areas are other factors, the report read.

Ben Drake, a longtime Wine Country farm manager, said once the population counts dropped, many growers cut back on their use of anti-sharpshooter pesticides to save money.

Applying half-treatments of the pesticides is worse than not using them at all because the sharpshooters can build up resistance, he said.