SALINA, Kan. (KWCH) All plants at Oakdale Park in Salina are very green.
What might be surprising is seeing that the water in the Smoky Hill River is also green.
Park officials say residents have nothing to worry about because that green layer on the water is not toxic.
"This is what we call duckweed and it's none toxic, it's just something vegetation that grows in water that doesn't have a lot of movement," said park superintendent, Rick Martin.
He says duckweed is in the water year round and when the weather warms up, it shows up.
"It'll kind of die out when we get into the hot part of the summer and then of course in the winter time, it will freeze up," says Martin. "A lot of these roots on here, they come together and that's what forms the mats that you see up there."
Martin says duckweed doesn't harm plants, animals or people.
"People just have a concern when they come down here with a pet or something, that the pet could get sick or something, but I don't believe that's going to happen," he says.
Martin says he has done tests on the water and sent it off for testing. The state confirms it is duckweed and poses no health threat.
Duckweed is also known to kill blue-green algae.
Currently, five lakes across the state are under blue-green algae warnings. That means the water is dangerous for pets or livestock to drink, and you should immediately wash your skin if you come into contact with it.