Leslie Leavens-Crowe, a partner at Leavens Ranches, looks over the healthy lemons trees at her grandparents lemon and avocado tree ranch in Santa Paula, California April 18, 2012. California orange, lemon and grapefruit growers are bracing for a deadly bacterial disease that could ravage the state's $2-billion citrus industry weeks after the first infected tree in the state was identified in a suburban Los Angeles yard. The tree ailment, called Huanglongbing or yellow dragon disease, is usually spread by the Asian citrus psyllid, an aphid-like winged insect that feeds on the leaves of citrus trees. REUTERS/Gene Blevins (UNITED STATES - Tags: AGRICULTURE BUSINESS)