The harmful aquatic plant known as giant salvinia was discovered in Ashdown’s Millwood Lake on Dec. 28 by Arkansas Game and Fish Commission and Army Corps of Engineers staff. It is the fourth known location in southern Arkansas infected by the invasive species.

Eric Brinkman, fisheries supervisor in the AGFC’s Hope office, said biologists collected several small clusters of the plant near Jack’s Isle along Little River. No large mats of the plant have been found yet, but it only takes a single piece to become an issue once the weather warms.

“It may look small at first, but this plant grows and reproduces extremely fast,” Brinkman said. “Under ideal conditions in warm weather, it can double in size in less than a week, and nearly every fragment of the plant can create a new mat.”

Giant salvinia, an exotic plant from Brazil, looks similar to duckweed, but is much larger and grows in large clumps. The free-floating plant has leaves between 1 to 2 inches wide.

Individual plants group together to form large floating mats that can impede boating as well as crowd out other plants and animals. When left unchecked they can choke out everything else.

“These mats can completely block all access to the water underneath,” Brinkman said. “They can get so dense a person could stand on them, so they are a serious issue.”

Brinkman said the AGFC and corps staff would conduct a larger search for the plant during the first full week of January in order to spray or remove the large mats. He encouraged anyone seeing the plant to contact the AGFC Hope Regional Office at 870-777-5580. 

Giant salvinia has continued a slow crawl across southern Arkansas since it was first detected in Smith Park Lake near Fouke in 2017. Its most likely source of transmission is on recreational equipment such as boats, trailers, duck-hunting decoys and other objects that are moved to different bodies of water during the year. 

“Boats and trailers can be major sources for invasive species like giant salvinia to hitch a ride to a new body of water, but we have increasing concerns that most of the cases we’ve seen are the result of duck-hunting equipment,” said Jason Olive, assistant chief of fisheries for the AGFC. “So we’re really trying to get the message to our hunters as well as our anglers to clean, drain and dry their equipment before moving to a new body of water.”

Olive said Louisiana spends more than $9 million a year to spray and control invasive plants, with a large portion of that focused on the single plant species.

Brinkman and Olive agreed the best partners in fighting giant salvinia and other invasive species are the anglers and hunters of Arkansas. They reminded the outdoorsmen to clean, drain and dry their boats, trailers, decoys and other equipment thoroughly after each use.

Visit https://stopaquatichitchhikers.org for more information on giant salvinia and other threats to our wetlands and fisheries.

Jan 5, 2021 - For more information on giant salvinia sightings in Arkansas, visit https://www.agfc.com/en/news/tag/giant-salvinia.