invasive aquatic plants – Aquarius-Systems

Herbicide Spraying Raises Drinking Water Concerns in Lake Okeechobee

Fri, 16 Oct 2026 17:41:27 +0000

The use of chemical herbicides to control invasive aquatic vegetation in Florida’s Lake Okeechobee is raising questions about potential impacts on drinking water. The lake serves as the primary drinking water source for customers of the Okeechobee Utility Authority, yet herbicides are routinely applied to manage invasive plants. According to a Lake Okeechobee News investigation, several of the herbicides used have restrictions requiring setbacks from drinking water intakes, temporary shutdowns, or water testing to protect water supplies.

The Florida Fish and Wildlife Conservation Commission (FWC) generally maintains a 500-foot buffer around the utility’s primary water intake. However, some herbicide labels specify restrictions extending as far as half a mile (2,640 feet), depending on the chemical and application conditions. Certain herbicides can also persist in water for days or weeks following application, raising additional questions about their potential movement through the aquatic environment.

When questioned about whether herbicides had been applied within these restricted distances, FWC officials stated that contractors follow product label requirements but did not provide the requested application records or distances. Although the investigation did not establish that drinking water had been contaminated, it highlights concerns surrounding chemical aquatic plant management and the importance of protecting water resources. It also underscores the value of considering nonchemical alternatives, such as mechanical harvesting, as part of responsible aquatic vegetation management.

Managing Invasive Frogbit with an Integrated Approach

Tue, 08 Sep 2026 16:01:49 +0000

More than 100 tonnes (approximately 110 U.S. tons, or about 220,000 pounds)of invasive Frogbit have been removed from properties around Anna Bay in New South Wales, Australia, following the discovery of the first known infestation in the Port Stephens region. Frogbit is a prohibited aquatic weed in New South Wales because of its ability to spread rapidly across the surface of waterways, crowding out native vegetation, smothering aquatic habitat and interfering with drainage.

Managing the infestation has required a coordinated response using multiple control methods. Large quantities of the invasive plant were physically removed, while herbicide treatments were also used as part of the effort to control remaining growth and reduce the potential for the weed to spread. The response demonstrates how an integrated management approach can be valuable when dealing with aggressive aquatic invasive species.

Early detection and continued monitoring will be important to preventing Frogbit from becoming established in the region. The project also highlights the importance of removing invasive plant biomass from waterways while combining appropriate management tools to address regrowth and protect surrounding aquatic ecosystems.

New Questions About ProcellaCOR and Eurasian Watermilfoil Management

Tue, 16 Jun 2026 18:12:24 +0000

Eurasian watermilfoil is one of the most widespread and challenging aquatic invasive plants found in lakes and waterways across North America. This submerged aquatic plant grows rapidly, forming dense underwater stands and thick surface canopies that can interfere with boating, fishing, swimming, and other recreational activities. In many water bodies, invasive milfoil can also outcompete native vegetation, reducing plant diversity and altering aquatic habitat.

Managing Eurasian watermilfoil often requires a long-term commitment and a combination of management techniques. Mechanical harvesting, hand removal, bottom barriers, biological controls, and aquatic herbicides are all commonly used to reduce infestations and improve waterway access. Each method offers advantages and limitations, and many lake managers rely on integrated management programs that combine multiple approaches to achieve their goals.

One herbicide that has gained significant attention in recent years is ProcellaCOR®, a selective aquatic herbicide designed to target invasive plants while minimizing impacts on many native species. Lake associations and resource managers across the country have used ProcellaCOR to combat persistent milfoil infestations, often reporting successful control of invasive growth and improved conditions for recreation and native plant recovery.

However, as with any management tool, questions remain about potential long-term effects and environmental persistence.

Findings from Lake George

Following a ProcellaCOR treatment in Lake George, New York, researchers conducted independent sampling of water, sediment, and aquatic plants to better understand how the herbicide behaved within the ecosystem after application.

According to the study, degradants associated with the herbicide were detected in the upper layer of sediment five months after treatment. Researchers also reported finding the herbicide’s active ingredient, florpyrauxifen benzyl, in deeper sediment layers more than a year after application.

These findings have generated discussion among lake residents, scientists, and resource managers regarding how herbicide compounds interact with lake sediments and whether long-term accumulation may occur under certain conditions.

Balancing Benefits and Concerns

For many lake communities, ProcellaCOR has become an important tool in the ongoing effort to control invasive milfoil. Dense infestations can significantly impact recreation, property values, water flow, and native aquatic plant communities. Effective control methods can provide substantial benefits when invasive species threaten the health and usability of a lake.

At the same time, some residents and environmental advocates have expressed concerns about possible unintended consequences of repeated herbicide use. Questions have been raised regarding sediment persistence, impacts on non-target organisms, and the long-term effects on lake ecology. While current research continues to evaluate these issues, many stakeholders are calling for additional monitoring and independent studies to better understand the full environmental picture.

The Importance of Integrated Aquatic Plant Management

The debate surrounding Eurasian watermilfoil management highlights the complexity of aquatic ecosystem stewardship. There is rarely a single solution that works for every lake or waterway. Factors such as infestation size, waterbody characteristics, management goals, budget, and environmental considerations all influence the selection of appropriate control methods.

Mechanical harvesting continues to play an important role in many aquatic plant management programs by physically removing plant biomass from the waterway without introducing chemicals into the ecosystem. Harvesting can improve navigation, reduce nuisance growth, and remove nutrients contained within the harvested vegetation. In many cases, harvesting is used alongside other management strategies as part of a comprehensive aquatic plant management plan.

As research continues and new information becomes available, lake managers, regulators, and stakeholders will need to evaluate all available tools carefully. Ongoing monitoring, transparent reporting, and science-based decision making remain essential for protecting both recreational access and long-term ecosystem health.

The conversation surrounding ProcellaCOR and Eurasian watermilfoil management is likely to continue as additional studies are completed. For lake associations and water resource managers, understanding both the benefits and potential tradeoffs of available management options remains a critical part of maintaining healthy and usable waterways.

Herbicide Costs vs. Mechanical Management on Northern Wisconsin Lakes

Thu, 18 Dec 2025 17:43:03 +0000

For over a decade, lakes across Northern Wisconsin have spent staggering sums of money attempting to control Eurasian water milfoil with herbicides. The Lower Eagle River Chain of Lakes Commission, formed in 2007 specifically to tackle this invasive species, is a case in point.

Eurasian water milfoil grows aggressively, uprooting native vegetation, disrupting aquatic habitats, and interfering with recreation. By 2013, the Commission was spending up to $250,000 per year on herbicide treatments to control approximately 300 acres of milfoil. Grants helped fund these efforts, but by the mid-2010s, funding had dwindled to around $50,000 annually.

After a decade of chemical treatment, the Commission made a bold decision to stop using herbicides altogether. The results? Within a few years, the milfoil population began rebounding. According to the aquatic ecologist who has monitored these lakes for 18 years, the plant is “too big, it’s too much” for manual removal alone, which costs roughly $2,500 per day.

The lesson is clear: eradication with herbicides is expensive, temporary, and environmentally damaging. Even if chemicals were used without regard for ecological impacts, controlling the entire population long-term is not practical.

Instead, a management-focused approach should to taken to target plants that interfere with navigation and recreation rather than attempting total eradication. Mechanical harvesting offers a solution; it doesn’t attempt to eliminate every plant but efficiently manages growth, maintains recreational access, and avoids repeated herbicide costs.

After more than a decade of observation, the evidence is in: spending hundreds of thousands of dollars chasing eradication with chemicals is far less effective than strategic, mechanical management. It’s time for a shift in mindset: toleration and control, rather than endless eradication efforts, may be the only sustainable way forward for our lakes.

Salvinia Threat Emerges in Lake Victoria Waters

Tue, 25 Mar 2025 20:16:39 +0000

A new invasive type of water hyacinth, Salvinia spp., has been discovered in Lake Victoria. It reproduces rapidly, doubling its biomass within 8 days due to high nutrient levels caused by human activities such as improper waste disposal and deforestation. Over 36 tons have already been removed, but the plant continues to spread, threatening fish populations, water transport, and biodiversity by depleting oxygen and reducing water quality.

The newly discovered Salvinia spp. in Lake Victoria likely entered the lake through contaminated fishing gear, boats, or water currents connecting nearby ecosystems. Unlike the regular water hyacinth (Eichhornia crassipes), which forms thick mats on the surface, Salvinia spp. spreads faster and is more resilient under varying environmental conditions. It depletes oxygen more aggressively, suffocating aquatic life and reducing biodiversity. This variant poses a greater ecological threat and requires immediate control measures.

The species negatively impacts fishing, tourism, and water supply, making urgent action necessary.

Mechanical Harvesting Tackles Curly-Leaf Pondweed in East Okoboji Lake

Mon, 18 Dec 2023 19:06:15 +0000

Invasive curlyleaf pondweed has been choking East Okoboji Lake, snarling boat propellers, burning up motors and shutting down swimming, tubing and other water sports in an area that depends on recreation.

The weed’s invasion is driving heated debates about how to control it — from using mechanical removal to administering herbicides that raise concerns about drinking water safety.

An aquatic weed harvester has logged 300 hours this spring, chopping and pulling out about 450,000 pounds of weeds from East Okoboji Lake. The plants are drying in a couple of remote spots, with the hopes that farmers might be able to use them for fertilizer.

Study Finds Plant Diversity Does Not Prevent Aquatic Invasions

Tue, 12 Dec 2023 16:20:49 +0000

A new study from the University of Minnesota challenges a common belief that lakes with diverse plant life are more resilient to aquatic invaders.

The study by the U’s Minnesota Aquatic Invasive Species Research Center looked at 13 years of vegetation survey data collected from about 1,100 lakes by the Department of Natural Resources.

The surprising results: Researchers found no evidence that having a diverse plant community somehow keeps invaders such as curly-leaf pondweed or Eurasian milfoil from taking hold.

Milfoil and Hydrilla the Evil Twins of Invasive Aquatic Plants

Fri, 08 Dec 2023 19:00:18 +0000

Eurasian water milfoil is an exotic invasive species that is thought to have been introduced to the U.S. in the 1800’s in the bilge of ships.
Once established milfoil can never be completely eradicated, but it can be managed with an aquatic weed harvester or repeat treatments of aquatic herbicides. Any relaxing on the spraying regimen however and it comes back as strong as ever.

Fishermen certainly appreciate a good balance of both milfoil and hydrilla for bass populations. Less vegetation and it doesn’t provide enough cover for juveniles, and too much makes it too difficult for the fish to navigate – and for the fisherman to locate them. Too much vegetation also causes difficulties for swimmers, skiers and boaters, as well as clogging powerplant intakes and municipal water systems.

Another definite drawback to a lot of milfoil is low oxygen content and increased eutrophication caused by the decaying of the plant.

After Milfoil Control, Curly-Leaf Pondweed Invades Lake Sunnyside

Fri, 01 Dec 2023 20:14:43 +0000

The war against milfoil in Lake Sunnyside, New York has largely been won — but at the cost of leaving the lake vulnerable to invasion from another plant.

Now, curly-leaf pondweed is taking over the lake, and stewards must fight that one too.

The problem was that milfoil occupied nearly all of the shoreline, the area where sunlight can reach the bottom of the lake, allowing aquatic plants to flourish.

Workers use chemicals that “wiped out” the milfoil but also all the other plants, said Protective Association of Lake Sunnyside board member Eric Sage.

“It devastated the fish population,” he said.

And it left a vacant area for other plants to use, he said. Another invasive species moved in quickly.

Herbicide to Treat Elodea Kills Native Aquatic Vegetation

Wed, 29 Dec 2021 21:49:49 +0000

Elodea is a plant commonly found in aquariums that, if released in the wild, will dominate certain lake or river habitats, choking out native vegetation and altering the food web at all levels.

It increases sedimentation rate, allowing more sediment to settle out of the water. And it can decrease the dissolved oxygen concentration in the water because it is growing so rapidly and using up all of that oxygen. But it also just displaces native aquatic plants, which are good forage for a variety of waterfowl species.

In addition, elodea can ruin the clear-water habitat needed by grayling and spawning salmon, and give an advantage to ambush predators like northern pike.

Applications of aquatic herbicide fluridone have appeared to have worked, and there is no elodea visible in Lake Hood (Alaska) now, but the herbicides killed most of the other plant life in Lake Hood as well.