"We need more rain or we'll see more problems (with saltwater) in another couple of weeks," said R. Ernest Girouard Jr., of Kaplan, La., a rice farmer who heads the Louisiana Rice Research Board.
Howard Cormier, the LSU AgCenter's county Extension agent in Vermilion Parish, said the past week has brought some relief from saltwater intrusion. But even more rain would help the situation further, he said.
About 1.5 inches of rain fell overnight Monday in Abbeville, and some parts of northern Vermilion Parish were drenched with 3 inches to 5 inches of showers, Cormier said.
"Anything we get is going to help. Even if it doesn't help with the salt water, it's going to help with the drought," Cormier said at Tuesday as another heavy shower fell on downtown Abbeville.
Girouard and Cormier said rice farmers battling saltwater intrusion from the Gulf of Mexico and the Intracoastal Waterway should monitor salt water content in their fields and in nearby ditches from which they pump water for irrigation.
Levels above 100 grains per gallon can harm young rice plants, and some parts of lower Vermilion are seeing those sorts of readings. Salt content at that level can harm rice plants before tillering – before the growth of new shoots on the plant. Most rice is at tillering or near that stage now, Cormier said.
"Rain will stave off major problems, but we need a little more," Cormier added. "A lot of the rainfall we've had has been absorbed, because the fields were so dry. We need 4 to 6 inches of additional rain."
Still, Cormier said his surveys indicate no damage to the rice crop at this stage.
The Lafayette area got slightly more than 1 inch of rain Monday night, a welcome relief, but not enough to signal an end to Southwest Louisiana's lingering drought. Only 0.19 inch of rain was recorded at the Lafayette airport for the entire month of May – a level far below normal.
Forecasts now call for the usual summertime pattern of scattered afternoon showers caused by a combination of high daytime temperatures and moisture from the Gulf of Mexico. But whether rain falls on a particular field is a hit or miss proposition, the experts point out.
Pumping even slightly salty water on rice fields can cause long-term problems, because the salt grains will settle out and remain concentrated in fields long after the water has evaporated, Cormier said.
Luckily, north winds have been blowing salt water out of the Mermentau Basin in lower Vermilion Parish and that is allowing fresh water in from White Lake, which helps rice farmers, Cormier added. Additional rainfall would also flush fields, further reducing the threat of salt remaining in the soil, he said.
"Even another inch or inch-and-a-half of rain would help," Cormier said.
Saltwater levels vary widely in lower Vermilion Parish and elsewhere along the South Louisiana coast. Farmers who want the latest readings can go the Internet for updates via the U.S. Army Corps of Engineers. (See this Web site for the latest from numerous test points: www.mvn.usace.army.mil/ops/sms/index.asp).
On Monday, readings at Forked Island were 38 grains per gallon, down from 50 grains per gallon on May 24. At the Leland Bowman Lock-East, Monday's reading was 137 grains per gallon, down from 144 grains per gallon on May 30.
On Tuesday, the readings at Schooner Bayou Eastside were 156 grains per gallon, the same as May 30 but down from a reading of 194 grains per gallon three weeks ago.
Randy McClain is a writer for the LSU AgCenter.