Ongoing battle against giant salvinia heats up

Published 8:01 pm Monday, May 20, 2013

Louisiana biological officials are using weevils and herbicides in an effort to get the upper hand against an aquatic plant that is spreading quickly in waterways around Southwest Louisiana.

Eric Shanks, a spokesman with the Louisiana Department of Wildlife and Fisheries office in Lake Charles, said the giant salvinia outbreak of 2013 is forcing the state to get creative.

“It is worse this year than it has ever been,” he said. “The plant will double its biomass. That means it can be in a 10-acre area and one week later it will cover 20 acres.”

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Native to Brazil, the plant has been found in Texas, South Carolina, Florida, Australia, New Zealand, New Guinea, Africa and India.

Giant salvinia is one of the worst aquatic plants that can be found in a water reservoir because as it spreads it blocks sunlight, therefore damaging an important life system.

During the fall of 2012, giant salvinia weevils were stockpiled and released into public areas where the plant has taken root. State official also sprayed herbicide in public waterways in the lower Calcasieu River area.

Shanks said the plant thrives in backwater swamps and marsh and gets flushed out into larger waterways.

The plant has been observed in Lake Charles, but won’t spread because saltwater kills it.

Salvinia thrives in fresh water. Near the Calcasieu River’s West Fork, efforts have been made to control its spread.

Shanks said environmental factors determine how prevalent the plant will be.

“It is not cold weather tolerant and this past winter wasn’t cold enough to impact the plant. Also, there was a lot of rain. Along with our efforts, we hope that as the summer progresses the dry air and water salinity will have an impact on the plant,” Shanks said. “The operative word is control because you can never achieve eradication with salvinia.”

State officials are communicating with private landowners in order to get more weevils in private waterways.

Shanks said boat owners should clean their boats after traveling in an effort to keep the plant from spreading.

Along with having the potential to wreck havoc on marine life, salvinia deters some from enjoying rivers and lakes.

In recent weeks, readers have called the American Press after observing the plant in different locations around the region.

Shanks said the plant has also spread around the state.””

Louisiana biological officials are using weevils and herbicides in an effort to get the upper hand against an aquatic plant that is spreading quickly in waterways around Southwest Louisiana. Eric Shanks

Rick Hickman””

a spokesman with the Louisiana Department of Wildlife and Fisheries office in Lake Charles

Rick Hickman