The federal government is getting involved in the fight against citrus greening disease, in hopes of saving Florida's _ and possibly the entire nation's _ citrus crop.

The U.S. Department of Agriculture announced Thursday that it's creating an "emergency response framework" to battle citrus greening. It will gather various groups, agencies and experts to coordinate and focus federal research on fighting the disease.

"We really need to be coordinating more effectively within the USDA and more importantly, with the citrus industry and state and local officials," said Agriculture Secretary Tom Vilsack. He added that since he came into office in 2009, the agency has spent nearly $250 million on researching and tracking the disease.

The citrus greening bacteria, which is spread by an insect, causes trees to produce green, disfigured and bitter fruits by altering nutrient flow to the tree, eventually killing it. It threatens Florida's $9 billion citrus industry. Growers and scientists suspect that many of Florida's 69 million citrus trees are infected, with some estimates as high as 75 percent. This year's orange crop is expected to be the smallest in 24 years, largely due to greening.

"If we don't find a cure soon, we won't be growing oranges in Florida much longer," Sen. Bill Nelson, D-Fla., said.

The new USDA group will help coordinate and prioritize federal research with the industry's efforts to combat the disease.

The USDA will also provide $1 million to support research projects and will launch a new section on its website about greening that will serve as an information clearinghouse.

It's especially important in Florida, where the state's famous orange crop is a big part of the economy, culture and history.

"We're treating this almost like a hurricane response," said Kevin Shea, the administrator for the USDA's animal and plant health inspection service. "The future of the citrus industry is at stake."

Florida's orange crop had $1.5 billion in sales in 2012, up from $1.3 billion the previous year. Citrus growers gave Florida 66 percent of the total U.S. market share. About 95 percent of the state's orange crop is used for juice.

Total citrus acreage is down 2 percent from the previous survey and the lowest since 1966.

"This announcement really addresses the urgency of the current problem of greening," said Mike Sparks, CEO of the Lakeland, Fla.-based Florida Citrus Mutual. "This new initiative announced by Secretary Vilsack could not have come at a better time."

The disease is transmitted by the Asian citrus psyllid. It's also known as HLB, or, in Chinese, Huanglongbing. The disease was first spotted in 2005 in South Florida and quickly spread throughout the citrus growing region.

Greening isn't just an issue in Florida.

California is the country's biggest supplier of fresh-market oranges, and its 285,000 acre-citrus industry is second only to Florida, according to California Citrus Mutual. California has seen one affected orange tree, in a Los Angeles County backyard.

Citrus experts on the West Coast said they are thankful that the federal government is devoting time and money to the problem.

"Our objective is to make sure USDA looks at this situation with the urgency we think this deserves," said Joel Nelson, president of California Citrus Mutual in Exeter, Calif. "This is a very good move on their part."

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