Despite a threat of rain and a peaking navel orange harvest, growers in Tulare County, the nation’s top citrus producer, could start a concerted spraying program in mid-December as they seek to eradicate a pest that could carry a deadly disease into their trees.

Officials with the California Department of Food and Agriculture told hundreds of growers who gathered in Tulare for an update on the pest that they will not face an immediate quarantine because of the discovery of a single Asian citrus psyllid in two different locations in Tulare County in November.

But they will have to use sprays in an 800 meter radius – about a half mile – of each of those finds in an effort to eradicate the pest. And there will be restrictions on movement of citrus in a five mile radius around each of the finds near Strathmore/Lindsay and Terra Bella.

(For more, see: California citrus growers schooling on Florida for coming HLB war)

The areas cover a total of about 163 square miles.

CDFA stopped short of a quarantine declaration, something that has been done in Southern California, because the Tulare County finds do not amount to an infestation.

But Robert Leavitt, CDFA’s director of plant protection and plant health, made it clear that further finds – additional adults or other stages of the insect such as eggs or nymphs – could change that picture.

“If there are a lot of adults, nymphs or eggs or the presence of HLB (huanglongbing, the tree-killing disease the pest can carry), then we would go to a standard quarantine.”

That could mean a 20 mile radius, he said, “by default, all of Tulare County.”

Ted Batkin, president of the California Citrus Research Board, said before the meeting that drew 400 people, “We hope this is a far as we have to go.”

Leavitt and others said the restricted and eradication zones could be in place for two years, but in six months their presence will be re-evaluated based on what is – or is not – found. The approach is being put into place, CDFA officials said, “Because there is a potential pathway for ‘hitchhiking’ ACP from Southern California quarantine areas along the Highway 65 corridor.”