From the Fresno Bee:

On a bright July morning, Adam Marler punched locations into a GPS device and set off in his pickup truck from Fresno into the back roads and citrus orchards of California's Central Valley.

His mission: to thwart the invasion of the Asian citrus psyllid, a pest the size of a rice grain capable of carrying a disease deadly to citrus trees.

The disease, known by its Chinese name Huanglongbing but also called "citrus greening," has devastated citrus orchards in Florida and other parts of the world, but it hasn't touched California's $1.8 billion industry. The Golden State ranks first in the nation in crop value and second after Florida in citrus production.

Marler, who works for the California Citrus Research Board, is one of 18 pest trappers who fan out daily across far-flung commercial groves to trap the psyllid and electronically map the tiny beast's every move.

"It's kind of like a war," Marler said, "and California is the last frontier."

For more, see: Calif. pest trapper helps thwart citrus disease