Snails Posing Problems in Florida Groves

Ernie NeffPests

Bulimulus sporadicus snails cling to a citrus tree.

A snail causing problems in Highlands County and South Florida groves “appears to be popping up all over the state,” said entomologist Lauren Diepenbrock. The University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) researcher identified the snails as Bulimulus sporadicus. “It was first documented in Florida in 2009,” Diepenbrock said. “Citrus is not the only crop to be dealing with it.”

The snails are attracted to irrigation components.

Highlands County Citrus Growers Association President Jim Snively recently wrote about the snails in the association’s newsletter, Citrus Connection. He stated that they are a problem in his company’s South Florida groves. “The snails are actually chewing on tender leaves and twigs and causing some dieback where populations are heavy,” he wrote. “They also get on the poly tubing, spaghetti tubing, the stake and the emitters of the irrigation system. When they get on the emitter, it can clog the emitter or distort and reduce the watering area of the sprinkler.”

“I have also heard from other growers in Highlands County that they have had issues with snails as well,” Snively added. “One grower said that they are finding them on resets inside the individual protective covers (tree nets), and are struggling to get spray coverage through the net to control them. So far, we have found that spraying Imidan at the maximum allowed rate will knock them back.”

Advertisement

Diepenbrock said, “It sounds like the current population is spotty, but gets very high very fast, suggesting a quick reproduction cycle and high reproductive state. This, of course, requires data to confirm. I know it has been a challenge in the Panhandle.”

According to Diepenbrock, snail damage depends on the scenario. “For mature trees, they are not likely to become a major source of damage, though this could change under extremely high population pressure. In the groves, they seem most interested in the microjets and weeds.”

“Many species in this genus of snails are decomposers, so that makes sense that they would be interested in declining weeds,” said Diepenbrock. “I suspect weed management will play a role in reducing their abundance. This could be a complete herbicide treatment of the affected areas or maintenance of habitat for predators like ground beetles that are known to attack snails and have done a nice job toward managing slugs in other systems.”

Bulimulus sporadicus

“For resets in bags, they are a problem,” Diepenbrock added. “Snails need to eat, and the young trees are what is available for food. I’ve been to one grove where they tried Imidan per the California recommendation for snails, but it didn’t really make a dent in them. That grove is currently testing a bait with metaldehyde as the active ingredient.”

Diepenbrock said she and other researchers are in the process of setting up lab-based screening assays to help determine what materials could have efficacy in the field. “Even with a good knockdown material, we still have to think about clearing the shells from the young snails from the irrigation lines,” she said.

Read an article by UF/IFAS researchers Davie Kadyampakeni and Arnold Schumann dealing with irrigation system maintenance, including keeping irrigation lines cleared.

See a 2017 UF/IFAS report on the snails’ invasion of Florida’s Panhandle.

Share this Post

About the Author
Ernie Neff

Ernie Neff

Senior Correspondent at Large