LGWCC Noxious/Invasive Vegetation Control
Overview
WHY IS LYNGBYA PROBLEMATIC?
Lyngbya is a filamentous cyanobacterium that has become increasingly problematic in southeastern waterways. This species can produce robust, mat-like formations that persist year-round along the bottom of a system, but as summer water temperatures rise, they begin to proliferate upwards through the entire water column. These unsightly and problematic mats can negatively impact aquatic ecosystems, impede recreational activities, and depreciate the aesthetic value of waterfront properties. Lyngbya may also produce organic compounds that create foul odors and negatively alter the taste of drinking water. In some cases, this species may produce cyanotoxins which most commonly result in skin rashes after contact. Lyngbya may spread by attaching to watercraft, animals, or through simple water movement via floating surface mats and can re-establish itself from a small amount of living material, further compounding management efforts.
Lyngbya Potential Health Concerns
WHY IS HYDRILLA PROBLEMATIC? Hydrilla, a non-native aquatic plant, has been known to be present in Lake Gaston since the 1980’s. At one time, thousands of acres of the lake were infested with the “weed.” Most lake residents recall when trying to boat or swim in the lake was an extremely unpleasant experience due to the proliferation of hydrilla vegetation. A major success story of controlling nuisance vegetation on Lake Gaston is the management of hydrilla. Today, in 2024, hydrilla is under control on Lake Gaston. It is not eradicated and probably never will be, due to its ability to remain viable as tubers rooted in the lake floor for many years. Hydrilla is still present in the upper reaches of many creeks and streams that feed into Lake Gaston and give the right environmental conditions it can spread very quickly! This is primary reason the LGWCC must continue to survey, monitor, and actively treat for hydrilla when conditions indicate the need.
Lyngbya Treatment Plans
Since 2015 the LGWCC has been conducting research to determine the most effective algaecides and treatment methods for lyngbya. Beginning in 2020 the LGWCC began operational treatments based upon available funding. The entire Lake Gaston shoreline is surveyed annually using a physical rake toss (by Lake Gaston Association volunteers) and sonar (by NCSU) to locate and determine lyngbya treatment areas for the LGWCC. During the mid-part of each month from April to September, residents in treatment areas should expect to see airboats utilized by the contracted application company, slowly moving along the shoreline applying lyngbya directed algaecides in established treatment sites. The chemical protocol that will be used at Lake Gaston includes chelated copper-based algaecides that are EPA-approved for aquatic use. These algaecides have a bright blue hue and will be observed in the water directly following applications but have no use restrictions in terms of irrigation, fishing, or swimming. Chelated-copper based algaecides remain the preferred control option for lyngbya, however effective treatment protocols require four to six consecutive monthly algaecide treatments to occur over multiple years. The success of treatments is also directly correlated with lyngbya growth and colonization, therefore, the timeline for achieving control is increased with greater infestation levels.
2024 Lyngbya Treatment Activity Press Release
2025 Lyngbya Treatments Week Beginning:
- April 14
- May 12
- June 9
- July 14
- August 11
- September 9 or 15
Treatment Maps
2024 Interactive Lyngbya Treatment Sites Map
Hydrilla Treatment Plans
The management of hydrilla has been ongoing for over 20 years using a combination of stocking sterile grass carp that feed on the plant and the strategic application of chemical herbicides in selected areas based on TAG recommendations to the LGWCC. The process of using grass carp and chemicals to treat hydrilla is a delicate balance to control the “weed,” while minimizing the negative impacts to native vegetation and wildlife in the lake. During the annual Lake Gaston Aquatic Vegetation Survey, the shoreline is sampled for vegetation including hydrilla and locations are identified that may require treatment to keep the “weed” in check.
All boat docks to be treated will be posted by PLM.
Treatment Dates:
- July 9-10, 2024
- May 14-15, 2024
- June 11-12, 2024
Treatment Maps
2024 Interactive Hydrilla Treatment Sites Map
Other Information/Maps
These interactive maps are used to track vegetation management operations, including public concerns and complaints regarding aquatic vegetation.
TBA