Weed Wars

Published 8:55 am Tuesday, January 15, 2013

JACKSON – It’s no secret the battle with hydrilla is a never ending one in Lake Gaston.

But recently Northampton and those surrounding counties on the lake gained an ally against the aquatic weed.

Brett Hartis, an aquatics extension associate with NC State University, spoke last week at the Northampton County Board of Commissioners’ meeting about his new role in the area as well as the importance of aquatic plant management and support from local government for those programs.

Hartis has been assigned to Lake Gaston and the surrounding counties. The position is the first aquatics extension agent in the state and it is funded by North Carolina, Virginia and the Lake Gaston Weed Control Council.

Hydrillia is an invasive aquatic plant with origins in Asia and began to show up in Florida in the 1950s. Hartis said the plant was often used in aquariums, and when owners disposed of the plants in ditches the plant began to grow in bodies of water.

While many waterways in Florida are covered in hydrilla, Lake Gaston is also one of the most impacted areas in the country. Hartis said the plant reproduces via fragmentation, both naturally and man-made (i.e. boat propellers), and by tuber roots in the sediment.

“What we like to compare it to is the Kudzu,” he said. “It’s Kudzu of the water.”

Hartis said hydrilla can compete against native species which are beneficial to ecosystems and food webs in the lake.

“It causes pretty severe fluctuations in water quality, specifically with dissolved oxygen and pH, so you can actually see fish kills,” he said.

The weed can also cause damage to water control structures as well as boat motors.

He said the local economy hinges on lake tourism (boating, camping, rentals, etc.) in the surrounding counties.

Local residents also rely on businesses around the lake businesses for goods and services.

Hartis added the presence of hydrilla can also decrease property value.

Hartis said of those Lake Gaston Association members surveyed approximately 21 percent resided in Northampton.

“Of those, 75 percent owned a house, 23 percent owned land and five percent own a business,” he said.

Hartis calculated land and house value within 1,000 feet of the lake to be at $252,523 per acre in Northampton.

“Yes, they’re a very small portion of the county, but that’s a pretty big number when you compare it to the rest of Northampton County with a value acre of $4,000 and a tax value of about $35 per acre,” he said.

Weed control funding from Northampton County goes toward three primary methods.

Herbicide application is the main method often used in high traffic areas in the lake (near boat docks). Hartis said the chemicals often provide quick results, but only lasts for approximately three to four years.

Grass carp are also an effective method against the invasive plant in low traffic areas. Hartis said a fish that weighs under 10 pounds can consume 150 percent of its body weight in plant matter each day. For those fish over 10 pounds they can consume approximately 30 percent of their body weight in plant matter.

The third method is re-vegetation, which allows the reestablishment of native plants in the area so they can shade out hydrilla.

Hartis said knocking down hydrilla each year helps to slowly deplete the plants’ tuber banks.

“Continued support from Northampton County is extremely important,” he said. “We need to realize this is a long term management plan and it’s never going to be a quick-fix. A realistic view is management, not eradication.”

Hartis said his specific goals are to improve the awareness in the lake community by having citizens contribute through interaction and volunteer opportunities.

Economically, Hartis said he wants to determine the importance of Lake Gaston and develop some outside funding sources for education, research and extension. He also would like to develop some long-term management goals for the counties.