Florida's $9 billion citrus industry is currently being threatened by greening, a disease spread by a bug known as "the yellow dragon."

The first case of reported greening came from China in 1943, where it is known as huanglongbing (yellow green dragon disease), The Associated Press reports. The disease got its name because its preliminary signs are turning the leaves of the infected plant yellow, resulting in the leaf looking like a dragon tail.

The greening disease came to the United States through a brown bug called the Asian citrus psyllid, according to AP. The bug eats citrus tree leaves, sucking the soft tissue out, and then leaves behind bacteria that clogs the plant's vascular system. This results in defoliation, the loss of fruits and damaged roots. The tree eventually dies.

There is no known cure for greening.

"It feels like you're in a war," Ellis Hunt Jr., whose grandfather started Florida's Natural juice company in 1922, said.

The bug is suspected to have traveled to Florida via an Asian traveler and was first noticed in 1988. Greening first appeared in the state in 2005.

Hunt estimates that 75 percent of his orange groves carry the disease. He spends about $2,000 per acre -- up 100 percent from a decade ago -- toward maintaining his product with nutrients and sprays to combat the greening and Asian citrus psyllid bugs.

"This affects the whole state: the economic impact, the landscape, the iconic image of Florida and how it has drawn people here to smell the orange blossoms in the spring and look forward to that Christmas gift of fresh Florida citrus," Adam Putnam, whose family has been growing oranges since the 1900s and works as Florida's agriculture commissioner, said.

According to experts, if the greening problem isn't fixed, Florida's iconic industry could die, causing packinghouses and processing plants to close and the loss of 75,000 jobs.

"A lot of people are looking for miracle cures, but the answer for greening will be a number of different pieces," Jude Grosser, a horticulture professor who works at University of Florida's Citrus Research and Education Center, explained. "... We need to give the tree a chance to beat the disease."

Despite the threat, some maintain hope that the United States will be the first country to stop greening.

"Irrespective of the challenges, Florida orange juice is not going to go away," Rick Kress, president of Southern Gardens Citrus, one of the Florida's biggest juice suppliers, said. "Florida had the disease first. We're on the forefront of dealing with it and finding a solution that will ultimately benefit the entire United States citrus industry."
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