Citrus Greening (Huanglongbing / HLB)
CRITICALCandidatus Liberibacter asiaticus
Overview
The most devastating disease of citrus worldwide, spread by the Asian citrus psyllid. There is no cure. It has caused billions of dollars in losses to the Florida citrus industry and threatens production in Texas, California, and other citrus-growing states.
- Type
- Disease
- Severity
- CRITICAL
- Source
- USDA APHIS
Symptoms
Asymmetric blotchy mottling of leaves, lopsided and bitter small fruit with aborted seeds, twig dieback, overall canopy thinning and decline, yellow shoots (yellow dragon symptom)
Affected Species
Geographic Spread
Treatments
Asian Citrus Psyllid Control
Aggressive insecticide programs targeting the psyllid vector, including systemic neonicotinoids and foliar sprays. Reduces disease spread but does not cure infected trees.
Removal of Infected Trees
Prompt removal of confirmed HLB-positive trees to reduce inoculum sources in the area. Required in some state regulatory programs.
Nutritional Therapy (Enhanced Foliar Nutrition)
Enhanced micronutrient foliar spray programs to maintain productivity of infected trees. Does not cure the disease but can extend productive lifespan. Effectiveness varies.
Recommended Products & Tools
Helpful supplies for managing Citrus Greening (Huanglongbing / HLB). Always read and follow label directions, and confirm a diagnosis before treating.
Protectant spray for many bacterial and fungal diseases.
For the rare case sealing is advised (e.g., oaks in oak-wilt season).
Sharp, clean cuts to remove affected wood — a tree-care essential.
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Frequently Asked Questions
What is Citrus Greening (Huanglongbing / HLB)?
The most devastating disease of citrus worldwide, spread by the Asian citrus psyllid. There is no cure. It has caused billions of dollars in losses to the Florida citrus industry and threatens production in Texas, California, and other citrus-growing states.
What are the symptoms of Citrus Greening (Huanglongbing / HLB)?
Asymmetric blotchy mottling of leaves, lopsided and bitter small fruit with aborted seeds, twig dieback, overall canopy thinning and decline, yellow shoots (yellow dragon symptom)
Where is Citrus Greening (Huanglongbing / HLB) currently found?
Citrus Greening (Huanglongbing / HLB) is currently active in Florida, Texas, California, Louisiana, Georgia, South Carolina, Alabama, Mississippi, Hawaii. It has been reported in 9 total states across the United States.
What plants are affected by Citrus Greening (Huanglongbing / HLB)?
Citrus Greening (Huanglongbing / HLB) affects Sweet Orange, Lemon, Grapefruit. Susceptibility varies by species.
How do I treat Citrus Greening (Huanglongbing / HLB)?
Treatment options for Citrus Greening (Huanglongbing / HLB) include: Asian Citrus Psyllid Control, Removal of Infected Trees, Nutritional Therapy (Enhanced Foliar Nutrition). Treatment approaches may include chemical, biological, cultural, and mechanical methods depending on the severity and context.