What if Citrus Greening is the 

Beginning of Future Pest & 

Disease Issues in US Agriculture?

March 11, 2015
Citrus Greening – AKA Huanglongbing

• Considered to be the 

most serious disease of 

citrus (NAS 2009)

– Bacterial disease

– Insect vectored

– First found in FL in 2005

• Coming on the heels of 

the citrus canker 

eradication project

– Grower aversion to 

removing trees
Public Enemy #1

Insect Vector -

• Diaphorina citri – Asian citrus 

psyllid; discovered in FL, June 

1998, now widely distributed
HLB Increasing Throughout the State 

October, 2005

2 counties
HLB Increasing Throughout the State 

April, 2006

12 counties
HLB Increasing Throughout the State 

January, 2007

14 counties
HLB Increasing Throughout the State 

June, 2007

24 counties
HLB Increasing Throughout the State 

February, 2008

30 counties
HLB Increasing Throughout the State 

August, 2008

32 counties
How Fast Does it Spread? Oct05-Mar06
How Fast Does it Spread? Apr06-Sep06
How Fast Does it Spread? Oct06-Mar07
How Fast Does it Spread? Apr07-Jul07
How Fast Does it Spread? Aug07-Oct07
The Florida Grower Journey 

Pictures of same grove and trees exhibiting disease over time.

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9/28/2015

Snapshots in time......

April 19, 2007 December 16, 2008

April 23, 2009 September 23, 2010
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October 21, 2011
June 13, 2012
May 16, 2013
December 1, 2014




2/11/15 Conference Call - APHIS Pest 

Detection and Emergency Response

• Representatives of appropriate agencies.

• Provided overview of total process on 

identification of new pest issue.

• Question – How would APHIS grade response 

and performance to the ACP?

– Broader and more full USDA response needed.

– Lack of process/system to ensure appropriate 

coordination and action.

– Going forward, more proactive and faster reaction to 

identified pest issues with strong future coordination 

and direction immediately.

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Summary

• HLB Citrus Greening Disease has been 

confirmed in the U. S. since 2005. 

• Significant financial support from the USDA is 

now in place. 

• What if the HLB disease is an indication of future 

Pest and Disease issues that could impact U.S. 

Agriculture? 

• How can the USDA be more proactive in 

addressing a similar situation?

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Research Subcommittee Statement

• The Fruit and Vegetable Industry Advisory 

Committee would like to commend the various 

functions and personnel of APHIS on their efforts 

and support of the Florida (and U.S. Citrus) 

industry in the current challenges faced by the 

industry in dealing with the Huanglongbing (HLB) 

greening disease. However, in retrospect, the 

overall response to the control of the insect 

vector, the Asian Citrus Psyllid (ACP), could have 

identified sources of funding for research and 

development of control procedures in a more 

expeditious manner. 

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Research Subcommittee 

Recommendations

• #1 – USDA should seek to develop a preemptive 

program for the identification of invasive pests 

and diseases that can have potential total 

destruction effects on current agricultural 

commodities.

• #2 – USDA should assign one (1) intra-agency 

function to be the coordinating entity to manage 

the total process for identified pest and disease 

issue(s), with supporting efforts from all other 

USDA functions as appropriate. 

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