MOULTRIE — Chet Powell knows that fighting weeds isn’t easy, even when those undesirables are growing in water instead of on dry land.

Powell, the manager at Reed Bingham State Park, said chemicals have helped tame the hydrilla that grows from the lake bottom, at least for the moment, but another nuisance species has made its presence known this year.

He is currently writing a grant application to deal with that pest, water primrose, after a joint operation with Florida last year that tackled a third species, water hyacinth, on the lake and on the Little, Withlacoochee and Suwanee rivers.

“Our concerns are (those) three plants,” he said. “Hydrilla affects the lake the quickest because it will tear up boats and jet skis. We have put $35,000 worth of chemicals in the lake. The problem is I don’t know if those chemicals will last to the end of the summer.”

There are a number of theories on how hydrilla made its way into the state’s waterways, including being dumped from aquariums, hitchhiking on the bottoms of boats and trailers used in Florida rivers and lakes, or even being transported by birds, Powell said.

Nationwide, the economic losses and environmental damage caused by exotic species is $120 billion annually, and $100 million is spent fighting them, said Kristina Summers, senior public relations and information specialist with the Georgia Department of Natural Resources.

The state currently is seeking input on a proposed management plan targeting invasive aquatic species, with a July 30 deadline.

The five-year plan is the first statewide attempt at prioritizing non-native species that threaten Georgia waters and identifying what can be done by a variety of organizations.

Besides hydrilla, an Asian/Australian water plant that has infested some Georgia waters, other problem aquatic species include the island apple snail from South America, and even feral hogs, which can impact streams and wetlands by rooting up soil and vegetation.

Part of the state’s plan is calculating the cost of the invasive species in the state, Summers said.

“Hydrilla can completely choke out the natives, it can completely out-compete the native plants ... and block out sunlight,” she said.

At Reed Bingham a weed harvester is being used along with two applications of pellets that attack the hydrilla, stunting the growth but not knocking out the infestation entirely, Powell said. He also is writing a $75,000 grant for a herbicide to attack the water primrose, which grows so thick it can choke the mechanical harvester.

“The problem with it is it can double, every couple of weeks it can double in size and area too,” he said.

Powell said that boaters can help prevent the spread of invasive species like hydrilla by checking and removing vegetation from trailers and boats before putting them into Reed Bingham. Likewise, they should clean vegetation from boats after an outing at the park to prevent spreading it to other bodies of water.

Water grasses can prove expensive to boat owners because they can clog intakes that provide water to cool motors and causing them to overheat, said Jay Wagner, owner of Recreation Outlet.

“It’s cost people from $100 to $1,000, is what it boils down to,” he said. “Running hot does blow up a motor. It gets expensive.”

Vegetation also can cause propellor slippage, he said.

At the pond at his North Veterans Parkway business, Wagner said, water grasses are now present, where a year and a half ago the water was free of them. Those grasses came in on boats brought in from repair.

To comment on the draft Georgia Aquatic Nuisance Species Management Plan, send an e-mail to jon.ambrose@gadnr.org, or write Jon Ambrose, Georgia Wildlife Resources Division, 2070 U.S. Hwy. 278 S.E., Social Circle GA, 30025.

A copy of the plan is available online at www.georgiawildlife.com, and from the Georgia Wildlife Resources Division office.