The San Bernadino region is among the areas whose citrus trees are under quarantine as of late. The reason: A fear of the spread of Asian citrus psyllids, aphid-like insects capable of devastating citrus crops. Trees should have a tag on them saying it’s forbidden to bring them out of Southern California, and if caught, the tree will be burned. According to San Bernadino and other California area pest control services, the psyllids could threaten California’s $1.8 billion citrus industry. San Bernadino exterminators have been called in to residential areas after sightings, but the main threat is that they are carrying huanglongbing, an incurable disease, harmless to humans, but extremely damaging to citrus fruit and trees.