Avoid Moving Citrus While Travelling to Prevent Spread of Harmful Tree Disease

Published: 07/10/2019



July 10, 2019



Phil Pitchford

Public Information Officer


[email protected]



Avoid Moving Citrus While Travelling to Prevent Spread of Harmful Tree Disease

Huanglongbing, or HLB, disease kills infected trees; there is no cure

RIVERSIDE, Calif. – Agriculture experts trying to stop a disease that kills citrus trees are urging Southern California residents to leave homegrown fruit at home when travelling this summer.

The disease, called Huanglongbing (HLB), has been found in trees in Riverside, Los Angeles and Orange counties, including five trees within the Riverside city limits. The disease, also called citrus greening, slowly kills infected trees, and there is no way to stop it once a tree is infected.

More than 1,000 square miles across Southern California are included in an HLB quarantine area. Information about the quarantine area can be found at CaliforniaCitrusThreat.org.

HLB is spread by a tiny insect, the Asian citrus psyllid, as it feeds on citrus tree leaves. While HLB is not harmful to humans or animals, there is no cure for the disease once it infects a tree. Experts advise owners of citrus to:

  • proactively inspect citrus trees for the Asian citrus psyllid and HLB monthly, and whenever watering, spraying, pruning or tending trees.
  • look for the Asian citrus psyllid. Adults are brown, about one-eighth of an inch long, and feed with their body at a 45-degree angle on citrus leaves.
  • be aware that symptoms of HLB include blotchy and yellowing leaves, premature and excessive fruit drop, lopsided fruit, and bitter, inedible fruit.
  • call the state’s pest hotline at 800-491-1899 if the pest or disease is spotted.
  • cooperate with agriculture officials who may ask to inspect or treat citrus trees.
  • visit a local nursery or garden center to get advice on products that can help protect citrus trees.
  • dry out citrus clippings or double bag them before disposal.
  • refrain from moving citrus plants, foliage or fruit as doing this may unknowingly spread the pest.

More information and photos of the Asian citrus psyllid and HLB symptoms are available at CaliforniaCitrusThreat.org.