Asian Citrus Psyllid and Huanglongbing Disease

The Asian citrus psyllid and the deadly Huanglongbing disease (HLB) that it spreads threaten citrus trees in backyards and on farms. The disease has destroyed the citrus industry in Florida and arrived in Southern California in 2008. It has been found as far north as San Joaquin county. HLB affects all types of citrus.

What is the concern?

  • The disease will kill trees in as little as five years.
  • There is no cure or effective control method for HLB.
  • Reducing the psyllid population helps to slow the spread of the disease.

Inspect your citrus trees for psyllids.

  • From spring through fall, look for psyllid eggs, nymphs, and adults on new leaves.
  • Adults are about the size of an aphid. The feed with their heads down and their “tails”
    in the air.
  • Nymphs are tiny and yellowish and they excrete white waxy tubules.

What are the symptoms of HLB disease?

  • Leaves show yellow mottling with patches of green.
  • Fruit is small, lopsided, and falls off the tree easily, while the juice is bitter.

What should you do if you think you have the Asian citrus psyllid or HLB?

  • Put a sample in a locking bag and bring it to your local UC Master Gardener office or your local Agricultural Commissioner office.
  • DO NOT move plants or clippings out of psyllid-infested areas, because they can spread the insect and disease.
  • For more information please go to the IPM website, www.ipm.ucdavis.edu