You have no doubt seen the green vegetation that is washing into Lake Charles from the Calcasieu River. It has been really thick on the west fork of the river. I was curious about what it was and how we can keep it from taking over.

Don Rivers


Giant Salvinia (a member of the fern family)plant originated in Brazil and South America. There is no telling exactly how it invaded our waterways. It could have been brought in on a boat or a bird could have given it to us as a present. It can travel on gators and otters. Tracking how it spread is an impossible task. We do know that it has basically invaded all of Louisiana's waterways. It started in North Louisiana and has worked it's way south. It is what you see along the shores of Lake Charles. It can double in size over a seven day period.

The Giant Salvinia invasion started in 2009. It has only taken three years to spread all over the state.The reason we seem to be seeing more this year is because of the mild winter we experienced. The plant can not survive freezing temperatures. The mild winter allowed it to flourish in the swamps and backwater. The spring rains have washed it into the main river channel and eventually into Lake Charles.

The good news is that it has gone about as far south as it ever will. Giant Salvinia does not tolerate salt water. When the salinity in the lake rises it will immediately die and sink to the bottom to decompose. The bad news is that it washes up on the beach.

The State of Louisiana has tried several methods to control the spread of Giant Salvinia including the release of weevils to a controlled area. Some herbicides have proven effective and salt water flooding of an area has shown excellent results.Weevils are currently being distributed to private land owners and spraying is taking place along the river. These pictures were taken from the shores of Lake Charles and show that we still have a battle on our hands.

Don Rivers