Bruce Schultz | 3/14/2006 4:07:22 AM
ALEXANDRIA – South Louisiana rice fields contaminated with salt from Hurricane Rita’s storm surge have shown some improvements, although not as much as expected, and salinity levels actually have increased in some sugarcane fields.
That was the word from LSU AgCenter experts at the Louisiana Agricultural Consultants Association convention last week (Feb. 15-17) in Alexandria.
In sugarcane fields affected by the storm surge, testing has shown salt levels actually have increased in recent weeks. In some areas the level climbed from 6,000 parts per million just after the storm to 8,000 parts per million in recent testing at soil depths up to 3 inches, according to Dr. Howard "Sonny" Viator, LSU AgCenter professor and coordinator of its Iberia Research Station.
Viator said hurricanes Rita and Katrina caused a 24 percent loss to the state’s sugarcane crop.
"Hurricanes caused more damage to sugarcane by flooding the crop than by the accumulation of salts on the soil," Viator said. Tidal surges affected or flooded about 37,500 acres, he said.
Viator said experts are not certain about the effects of salt levels on future cane crops. "We can only speculate at this time," he said.
As for rice, LSU AgCenter agronomist Dr. Jason Bond said rice fields still need rainfall for a good flushing.
"What we hoped would happen has not happened," said Bond, who works at the LSU AgCenter’s Rice Research Station at Crowley. "I’m more frustrated now than when we started."
Bond said he’s not comfortable advising farmers that their crop will be safe even if it’s planted in soil with salt less than 1,000 parts per million. "All we’ve got is seedling data at this point, and too many factors can interact to cause damage," Bond said.
LSU AgCenter rice specialist Dr. Johnny Saichuk said experts had anticipated that seasonal winter rains would rinse the salt from the soil.
"We have not had a real good flushing rain," Saichuk said of the conditions that have followed the storm.
On the other hand, Saichuk predicted that by this time next year most areas should be back to normal. But the highly contaminated areas could be years away from planting, the experts caution.
Saichuk said he has talked with crop insurance agents, and it appears some coverage may be available for farmers who cannot plant their crops because of salty soil.
In addition to the problems hurricanes created for farmers, the crop consultants convention focused on Asian soybean rust.
Even though Louisiana farmers were spared from a major Asian soybean rust outbreak last year, they shouldn’t let their guard down, LSU AgCenter experts advised.
"We just need to pay attention," said Dr. Boyd Padgett, LSU AgCenter plant pathologist. "Don’t get caught off guard."
Padgett said the Mato Grasso area of Brazil has a severe rust problem because the crop is grown there almost year-round.
Brazilian farmers have to harvest at least 50 bushels per acre to break even, said Dr. Ray Schneider, LSU AgCenter plant pathologist, and they are spraying three to six applications of fungicides.
"They’re talking about getting out of soybeans in Mato Grasso and going into some other crop, probably sugarcane," Schneider said.
Schneider, who in 2004 found the first incidence of Asian soybean rust in the United States, said the disease usually shows up on the first true leaves of the plant about two to three weeks after planting.
The disease was found on kudzu, which can harbor it during the off-season for soybeans, in Louisiana this November, Schneider said.
Louisiana’s low rainfall last year probably prevented any outbreaks in 2005, according to the experts.
"Normally, the weather conditions here are very conducive for disease development," Schneider said.
Sampling with spore traps has detected Asian soybean rust spores as far north as the Great Plains states, he said, but strangely no spores were found in traps in Georgia where the disease actually hit soybean fields in 2005.
Florida farmers had to fight Asian soybean rust last year, Schneider said. One grower was limited to less than 30 bushels an acre because he waited a week too long to spray fungicides, Schneider added.
Schneider said a Georgia researcher learned that rust could get out of hand and could not be controlled if spraying was delayed by about a week after the first occurrence of the disease.
In addition to those comments, LSU AgCenter plant pathologist Dr. Clayton Hollier warned Friday (Feb. 17) that 2006 could be the year Asian soybean rust really strikes Louisiana beans.
"The recently announced confirmation of Asian soybean rust in central Mexico could change the dynamics of rust development in Louisiana," Hollier said. "It is a more likely source of inoculum for our area due to prevailing southwest to northeast wind and storm movement."
An Asian soybean rust risk management workshop will be held from 9 a.m. until 1 p.m. March 1 at the LSU AgCenter’s Scott Research, Extension and Education Center in Winnsboro. To register, contact Hollier at (225) 578-4487.
In other matters during the consultants meeting, Carol Pinnell-Alison, who has served as an LSU AgCenter county agent in Franklin Parish for 17 years, received the annual Louisiana Agricultural Consultant Association’s County Agent Award.