Florida produces over 70% of the US citrus supply but its industry is threatened by citrus greening, a bacterial disease spread by the Asian citrus psyllid. Citrus greening causes fruits to become bitter, leaves to turn yellow, and trees to die within 5 years. While incurable, farmers can help prevent the disease's spread by scouting for psyllids weekly and removing infected trees. Researchers are also developing citrus hybrids resistant to greening in hopes of protecting Florida's largest export industry.

1. Knowing the Pests That Are
Killing Florida's Citrus Trees
U.S. Lawns

2. Florida is the United States’ go-to when it comes to citrus, as the state provides more than 70% of the
country’s supply, according to its tourism arm Visit Florida. It remained true in recent years, even with
the crop destruction caused by Hurricane Irma, the U.S. Department of Agriculture says in their “Citrus:
World Markets and Trade” report. Though it still maintains a significant lead against citrus-producing
states like California, a parasite and the bacteria it carries has been threatening Florida’s production for
years now.
Green Isn’t Always Good
Citrus fruits in cities like Clermont, Florida are being infested by what’s known as the “citrus greening.”
It’s caused by an insect called the “Asian Citrus Psyllid” that saps nutrients out of citrus leaves. It may
also infect the plant with a bacteria called Candidatus Liberibacter that causes “Huanglongbing” (HLB)
disease that can shut down a healthy tree in as little as five years, Newsweek says in an article called

3. “America's Citrus Fruits are Being Decimated by an Incurable Disease—We Need GM Science To Save Them.”
And the Florida Department of Citrus stated in a post called “A History of Citrus Greening” that this
infestation has been going on since 2005.
According to the University of California’s Agriculture & Natural Resources article on the Asian Citrus
Psyllid, HLB causes fruits to become smaller and bitter than usual. The whole plant also suffers from
discoloration, as leaves turn yellow and the fruit itself stays green -- hence, citrus greening. In about five
years, the plant stops bearing fruit and dies. The infection process is so slow that trees don’t show signs
of the disease until about two years. To add insult to injury, HLB is incurable, and it’s spread to other
states like California, Arizona, and Texas.

4. Looking at the Possible Solutions
The University of Florida’s Institute of Food and Agricultural Services (UF IFAS) says that, while the
disease is incurable, both farmers and commercial landscape service providers can take measures to
prevent it from infecting their citrus trees. These efforts include scouting for Asian citrus psyllids on
leaves weekly, spraying active ingredients on them like petroleum oil and chlorpyrifos to discourage
psyllid growth, and immediately removing infested trees to make sure they don’t spread the disease to
other plants.
Major producers may be incentivized to plant hybrid trees that the plant biologists at UF IFAS developed,
according to the Newsweek article. These trees are imbued with a gene from the Arabidopsis plant that
makes it resistant to greening.
Citrus fruits are one of the state’s biggest exports. As such, it’s imperative that its growers protect their
crops from incurable diseases like greening. With prevention methods and genetically engineered versions
of citrus trees being developed continuously, the future now looks as bright as the Florida sun.

5. Sources
https://uslawns.com/locations/fl/clermont/
https://www.visitflorida.com/en-us/eat-drink/facts-about-florida-citrus-oranges.html
https://apps.fas.usda.gov/psdonline/circulars/citrus.pdf
https://www.floridacitrus.org/newsroom/citrus-411/citrus-greening/a-history-of-citrus-greening/
https://www.newsweek.com/america-citrus-greening-decimated-industry-gmo-science-huanglongbing-
1359911
http://ipm.ucanr.edu/PMG/r107304411.html
http://blogs.ifas.ufl.edu/manateeco/2017/10/06/citrus-greening-remains-problem-backyard-citrus-
trees/