For the first time, giant snails wipe out a Louisiana rice field

• By Bruce Schultz •

channeled apple snails

Channeled apple snails were separated from the crawfish during harvest. Six to twelve crates were filled each day, and fields were harvested three times per week. the fisherman pulled his traps in late January 2018 because the snails were just too much — photos by Dustin Harrell, LSU AgCenter

An invasive species of snails has wiped out a 50-acre field of rice, the first time the pest has been known to do that in Louisiana.

LSU AgCenter entomologist Blake Wilson said damaged rice and channeled apple snails were found throughout the field.

“There was no trace of rice. If you didn’t know better, you’d think it was a snail production farm,” Wilson said.

He said the farmer knew snails were present in high populations in some fields, because he had previous problems with the snails disrupting crawfish production. The damaged field had been flooded throughout the winter, and extremely high snail infestations were present when it was water-seeded with rice.

“That’s the worst-case scenario,” Wilson said.

The farmer recalled that a lower population of snails was in the field last year, but no damage to rice occurred. This time, however, the snails decimated the rice seedlings.

The farmer had a problem two years ago with snails clogging his crawfish traps. The field is irrigated with surface water that comes from a bayou that flows into the Mermentau River.

apple snail damage

Rice plants were damaged by apple snails in a 50-acre field in southwest Louisiana.

Wilson said he wants to know why the snail population was so high in this field compared to nearby fields. The farmer plans to replant and control the snails with copper sulfate.

AgCenter rice specialist Dustin Harrell said apple snails have been a problem in Texas rice fields.

“Most of it is from clogging drains and causing breaks in the levees,” he said. “This is the first time in North America with significant damage in a stand of rice.”

Bruce Schultz is assistant communications specialist at the LSU AgCenter. He may be reached at BSchultz@agcenter.lsu.edu