By Vicky Boyd

More sweet orange scab has been found in Texas and in 15 Louisiana parishes, according to the U.S. Department of Agriculture's Animal and Plant Health Inspection Service.

The disease was found in 11 of 12 samples collected from residential trees in Hidalgo County, Texas.

Yesterday, APHIS confirmed the disease in neighborhing Cameron County, says APHIS spokesman Larry Hawkins.

This is in the primary citrus-production area of the Lone Star State.

Crews will continue to conduct delimiting surveys to determine the extent of the infestations.

All property owners have received emergency action notices, which prevent them from moving any host plant material off their properties, Hawkins says.

The original Texas finds in August were in Orange and Harris counties near Houston, more than 300 miles from the state's citrus-producing region along the Rio Grande River.

In addition, sweet orange scab has been confirmed in a total of 15 Louisiana parishes, Hawkins says.

They are Orleans—where the original find was made in a residential lime tree, Calcasieu, Vermillion, Lafayette, St. Martin, St. James, St. Charles, East Baton Rouge, West Baton Rouge, Iberville, Ascension, Beauregard, St. Tammany, Plaquemines and Tangipahoa.

With the recent additional finds, some researchers theorize that sweet orange scab may have been around for a lot longer than preious thought.

Mani Skaria, a plant pathologist at the Texas A&M University-Kingsville Citrus Center, says he believes better disease detection and identification methods recently have enabled scientists to differentiate it from the common sour orange scab.

Sweet orange scab is a fungal disease that creates unsightly blemishes on sweet oranges, rendering unmarketable in the fresh sector.

It can be controlled with commercial fungicides.

For more information about sweet orange scab, including photos, click here.