California fighting to save disease-threatened citrus trees Agents from the California Department of Agriculture are patrolling residential neighborhoods in the suburbs of Los Angeles looking for lemon and orange trees suffering from the "yellow dragon disease", which is fatal to citrus fruits. The goal is to treat diseased trees before the bacteria spreads to the center of the California, whose 120,000 hectares of citrus orchards make the state the largest producer of citrus fruits in the US. IMAGES AND SOUNDBITES