From the Associated Press:

The ubiquitous backyard citrus tree, symbolic of California's agricultural abundance, is front and center in the battle now under way to save the state's nearly $2 billion citrus industry.

State bug detectives fanned across this suburban Los Angeles neighborhood Monday, vacuuming backyard trees with bug catchers, setting traps and taking tissue samples from citrus in a frantic effort to stop the spread of a deadly disease detected there last week.

"You can treat commercial groves with pesticides, but you can't do that in downtown LA," said Larry Hawkins of the U.S. Department of Agriculture, underscoring the difficulty in treating an agriculture disease in an urban landscape.

The confirmed detection of the bacterial disease huanglongbing — more commonly called citrus greening — in a backyard lemon hybrid was the moment industry officials had feared since 2008. That's when the only bug that transmits it was first discovered in the state that produces 80 percent of the nation's fresh orange supply.

For more, see: Bug hunters fan across LA to stop citrus disease