Outbreaks of citrus canker in St. Lucie and Indian River counties in east-central Florida have agriculture officials scrambling to stop the spread of the fungal disease, a state agriculture official said, according to a Dow Jones report.

Canker has been found in five commercial groves - some grapefruit and some orange - and the USDA is now sending 60 people to survey and inspect the affected and surrounding areas. They will join 20 Florida state surveyors already in place trying to stop the disease's spread, Denise Feiber, a spokesperson with the Florida Department of Agriculture.

"We've had a few additional outbreaks in some additional groves in St. Lucie County. I think we are up to five groves where we have found positive trees in St. Lucie County," Feiber said.

Canker also was discovered in the Cobb Grove, a commercial operation in Indian River County. However, that outbreak has been "completely controlled" and approximately 2,100 trees were destroyed, she said.

Residential outbreaks of canker have been found in the town of Sebastian, in Indian River County, as well as Port St. Lucie in St. Lucie County. St. Lucie County is Florida's third-largest producer of oranges and Indian River is the seventh largest. Both counties are also large grapefruit producers. One of the groves in St. Lucie did not have a positive finding of canker but was included in the "exposure zone" because it was located within 1,900 feet of a mobile home park in Spanish Lakes Fairways, in the Ft. Pierce area, in which canker was discovered. About 7,000 trees in that grove were destroyed.

"The positive trees have all been pushed (uprooted) and once it's determined what the total exposure zone is then we'll be pushing and burning the additional trees. We hope to get that completed within the next month," said Feiber.

Citrus canker is a highly contagious plant disease that causes lesions on fruit and can eventually weaken and kill the trees. Officials believe the hurricanes that hit the state late last year were responsible for spreading the canker.