AUSTIN, Texas — Lady Bird Lake is looking murky, and it's because of a native Texas plant. The scientific term is cabomba caroliniana, but it's most commonly known as fanwort.
"It is a plant that does really well under certain environmental conditions if it's got a fairly rich, nutrient rich sediments," said Dr. Brent Bellinger with the City of Austin's Watershed Protection Department.
Fanwort grows here in Austin, in Lady Bird Lake and Barton Springs. The plant is in the water all year, but during the summer, it grows to be between 15 to 20 feet.
"You can see a lot of floating masses around the lake," Bellinger said. "Because of how prolific it can grow, it'll top out and it'll kind of create these rafts that a lot of people are seeing out here."
The plant isn't poisonous or harmful, but people in the lake can get tangled up in it.
"Their oars and paddles are getting tangled up in it," Bellinger said. "You know, swimming is banned in Lady Bird Lake – obviously, that would be something of a of a risk, is swimmer entanglement."
Fanwort can also make it harder for people to push through the water because the masses of this plant are so large. The good news is if something does get tangled up in fanwort, it breaks apart easily.
"But it's a pain," Bellinger said. "It's a nuisance ... constantly have to clean it. That's just the reality ... of these natural water bodies."
While it might not be a pretty sight to see, this plant is incredibly beneficial for the ecosystem.
"They're taking up nutrients," Bellinger said. "They're creating habitat for aquatic bugs. They're helping fuel the food web that, you know, lends itself."
Fanwort also helps soaks up nutrients that contribute to the formation of toxic algae.