Watercress (nasturtium officinale) is native to Eurasia, imported to the U.S. as a spicy cooking herb. It is a healthy low-calorie vegetable that when neglected can be a problematic invasive weed.
Watercress is an emersed weed found in shallow areas near the shoreline. It has alternate leaves with the end leaf not paired and a cluster of white 4-petaled flowers that rise above the top of the weed.
Cutting only makes the problem worse.
1) Dig up Watercress root and all before it begins to flower. Remove weeds to an area away from shoreline and allow it to dry.
2) 2,4-D herbicide is a systemic option that is best applied early spring at the first sign of new growth prior to seed. This option will kill the entire weed root and all. Repeat treatment may be needed 3-5 weeks after the first application if weeds begin to show signs of recovery.
3) Glyphosate herbicide is a systemic option that is best applied mid-season when growth is above the water level and in full bloom. This option will kill the entire weed root and all. Again, repeat treatment may be needed 3-5 weeks after the first application if weeds begin to show signs of recovery.
A customer recently contacted us regarding lake weed & algae control. Below is his question and our response.
For years I have been waiting for you to include Cabomba or Carolina Fanwort in your printed catalog so I could show my fellow pond residents that particular species is recognized invasive up here in MA. I have one neighbor in particular who claims the weed has been in the pond her whole life so she thinks it belongs here. She does not accept that it is a non native species that was introduced many years ago. I need you to list that species not only in your catalog but also on your website so I can direct my neighbors to your site to prove what I have been trying to tell them for 13 years.
Fanwort, cabomba is an invasive aquatic exotic perennial that primarily spreads by stem fragmentation of rhizomes that threatens inland lakes and ponds. It can overtake native plants, have an impact on native animals and reduce recreational water activities such as boating, swimming and fishing.
Fanwort is native to South America, it is a popular aquarium plant and thought to have been brought to the U.S. through the aquarium trade.
Fanwort has intricate fan shaped leaves with white-pink floating flowers. Submersed leaves secrete a sticky mucous which covers the foliage. It is very aggressive and can rapidly force out native aquatic plants in depths up to 3 feet. Fanwort reproduces from small fragments that may survive free floating up to 8 weeks. Once the invasive species takes root it can be hard to eradicate.
Chemical options know to be effective are fluridone, 2,4-d and diquat
Furidone is a systemic herbicide that is only effective when it is treated at 10-20 ppb.
2,4-d is a systemic herbicide that is absorbed and moves within the weed. It is used with a high degree of success. After treatment with 2,4-d, all Cabomba is killed.
Diquat, is a contact herbicide that acts quickly and will kill the foliage it touches.
When using liquid contact herbicides, thorough coverage of the weeds' foliage is necessary for good results. Inject underwater with a pressure sprayer for foliage beneath the surface. Apply on a calm, sunny day. Do not treat if rain is expected within 8 hours.
Physical removal works by hand pulling. This option works before Fanwort takes hold and only a few weeds need removal.
Drawdown works if the target area can truly be completely dried and/or frozen for at least one month. This is hard to do because muck sediments often stay moist and protect the weed root systems and allowing considerable survival.
There are no biological controls for this species.
Prevention is key, always check to make sure there aren’t plants attached to your boat or trailer before you enter or exit your lake or pond.
ALLIGATORWEED (alternanthera philoxeroides) was first reported in the U.S. in 1897. It originated in South America and was probably introduced in the U.S. through ballast water. It is now also considered an invasive weed in Australia, China, New Zealand and Thailand.
Alligatorweed has long elliptical leaves that branch opposite on hollow stems that stand 4 feet high. It has a whitish papery ball-shaped flower that closely resembles clover. The flowers are located on spikelets that rise from the leaf base. Alligatorweed spreads by seed and fragmentation.
When Alligatorweed invades waterways it can reduce flow, prevent light penetration and deplete oxygen due to weed decay. This oxygen depletion can reduce both waterfowl population and fish activity. It also makes a perfect habitat for breeding mosquitoes that can potentially carry disease like West Nile or Encephalitis.
Mechanical control has not been shown to be effective because Alligatorweed can easily root from fragmentation.
2 great options for Alligatorweed control are biological & chemical control.
Biological control can be obtained with Alligatorweed Flea Beetles, Alligatorweed Thrips and Alligatorweed Stem Borer.
Chemical control can be achieved with 2,4-D or glyphosate. 2,4-D is best applied early spring at the highest labeled rate as new weeds begin to appear. Glyphosate is best applied mid-season when growth is up and in full bloom. Repeat treatment may be needed to kill the entire root system.
There is a chance of oxygen depletion after chemical treatment caused by weed decomposition. This oxygen depletion can adversely affect fish. If your pond is heavily infested, treat in sections. Let each section of weeds decompose before treating another area.
Yates County legislators want to hear from the public about the potential for a local law to prevent the spread of invasive, non-native species into the waterways of the county.
PHOTO/ Robert L. Johnson
Hydrilla is an aggressive invasive species that can grow up to a foot a day, say experts.
The Yates County Legislature will not vote on a proposed local law intended to prevent the introduction and movement of aquatic invasive species in Yates County waters during their April 8 meeting as previously planned because additional work needs to be done on the draft law, explains District III Legislator Dan Banach of Milo, who is chairman of the Public Works Committee.
A public hearing on the proposed law will still be held at the beginning of the 1 p.m. meeting Monday.
Although some non-native invasive species have already found their way into the local lakes and waterways, the proposed law was spawned by increased concerns over the spread of hydrilla, an aggressive water weed that has gotten a foothold in the Cayuga Lake Inlet.
The law's intent is to protect the ecology of the navigable water bodies in the county by preventing the introduction of the invasive species.
James Balyszak, who is the Ithaca-based Hydrilla Program Manager through Cornell Cooperative Extension, says at this time the hydrilla infestation is limited to the Cayuga Inlet.
"No hydrilla has been found in Cayuga Lake, or any of the neighboring Finger Lakes (thankfully), and our eradication efforts in the Inlet are helping. In September of 2012, hydrilla was discovered in the Erie Canal in North Tonawanda (near Buffalo).This is not related to the Cayuga Inlet discovery, or the Finger Lakes area exactly, but it is a discovery in another part of New York State," he explains.
According to information provided by the Cornell Cooperative Extension, hydrilla can grow up to a foot a day, and forms a thick dense mat that will block sunlight, kill native plants, and reduces oxygen in the water, altering the fish habitat. Its growth can obstruct boating, swimming and fishing and block intakes at water treatment plants.
Among other things, the proposed law will prohibit the launch of a watercraft into a navigable body of water with any plant or animal or parts visible or attached to any part of the watercraft, including in live wells and bilges, the motor, rudder, anchor or other areas, including the trailer.
Warren, Tompkins and Schuyler County have adopted similar laws while Essex and Washington County are considering laws. In addition, the village of Lake Placid in Essex County and seven towns — Lake Pleasant in Hamilton County; Santa Clara, Brighton Harrietstown and Franklin in Franklin County; and North Elba and Schroon in Essex County — have all adopted laws. Two other towns in Herkimer and Oneida Counties are considering laws.
If convicted of violating the law, a person faces a fine of $250 or up to 15 days in jail.
When the legislature set the public hearing, District 2 Legislator Richard Willson objected, voting no, saying he thought the effort was a "feel good thing" about the lake, commenting that laws have never been considered to stop the spread of invasive species such as hogweed. Noting that the most frequent transport of seeds is through the wind and via birds, Willson said he doesn't feel a law like this can be enforced and he thinks the effort should be put into developing a plan for when the species do enter the area.
He said he feels effort should be put into education.
Elizabeth Newbold of Cornell Cooperative Extension of Yates County explained that research shows the hydrilla is transported by watercraft.
She also compared the proposed law to similar laws about transporting firewood within New York State, an effort to restrict the movement of non-native insects.
Balyszak says there is a myriad of printed materials from multiple conservation agencies regarding Hydrilla, its infestation and effects, and ways the citizens/boaters can identify, report, and prevent the spread of hydrilla and other invasives.
"During the 2012 season the Finger Lakes Institute managed the Boat Steward Program, which put trained individuals at boat launches on several of the Finger Lakes. These trained individuals helped to educate boaters on clean boating practices, the threat of hydrilla and other invasives, and provided free boat/trailer inspections to boaters (on a voluntary basis after boater consent)," he said, adding, "The Boat Steward Program was quite successful, and will be implemented again this year."
You can find more information, as well as numerical results of the Boat Steward Program at this link: http://flisteward.wordpress.com/
Banach introduced the law, and explained it is an effort to help protect the water inlet for the village of Penn Yan, which supplies water to about 1/3 of Yates County's households.
"Granted, it may be difficult to enforce, but it may keep some out," he said.
Mark Morris, who also represents District III, said the Keuka Lake Association and Seneca Lake Pure Waters Association are behind the efforts to try to reduce the impact of the invasive species.
The legislature's meeting begins at 1 p.m. April 8 in the legislative chambers.
A customer recently contacted us regarding Parrot Feather control. Below is his question and our response.
I have a small fish pond about 20’ x 30’. I have a weed called “Parrot Feather” that took over the pond which is hard to kill. I would like to try your product. Since this product is in a pellet form, will the fish eat it? Will it harm fish, frogs or crawfish? Can you also tell me what the proper way is to dispose of the stuff removed from the pond, will it propagate on land?
Aquacide Pellets are an excellent systemic option for Parrot Feather control. Aquacide Pellets will kill the entire weed root system and all. A 20’ x 30’ pond is 600 sq. ft. and would require 2 lbs. of Aquacide Pellets per treatment. For best results, apply early season when new weeds begin to appear and are actively growing. Repeat treatment 3-5 weeks after the first application if weeds show signs of recovery. Initial effects will occur within 7-10 days, full control may take up to 5 weeks.
When applied according to label directions, Aquacide Pellets will not harm, fish, frogs or crawfish.
If you do physically remove aquatic vegetation do not leave fragments in pond or on the beach as damp fragments will re-root in water or moist areas. Haul all aquatic vegetation far from lakefront to a dry area. Dry fragments make excellent organic garden mulch that can be turned into soil or placed on surface to discourage terrestrial weed growth in your garden.
If there is an excessive amount of "muck" or dead vegetationat the bottom of the lake or pond, which can sometimes occur in settings that are conducive to the parrot feather growth, you can use AquaClear Pellets in conjunction with the Aquacide Pellets to help clear the sediment from the treatment site. If you decide to use the AquaClear Pellets, they can counteract the Aquacide so we recommend waiting three weeks after treating the parrot feather before switching to weekly applications of the AquaClear.
WHAT CAN BE DONE TO CONTROL EXOTIC AQUATIC PLANTS?
Prevention is the first defense in exotic species control. However, once an exotic weed has colonized a lake, early detection and a rapid response approach is the most effective method to control the spread of the plant. What approach works best in a given situation is dependent on several variables.
Many exotic plants are transported on boats and boat trailers. If you trailer your boat from lake to lake, wash before re-launching.
Monitoring is key to early detection. Plant surveys are often conducted with a global positioning system that allows the specific location of aquatic plants to be documented.
This is commonly used to control invasive exotic plants (including Eurasian Milfoil). There are currently more than 300 herbicides registered with the EPA. Of those only about a dozen are approved for use in the aquatic environment. There are 2 basic types of herbicides: systemic and contact.
Systemic herbicides (Aquacide Pellets, Restore Liquid and Shore-Klear Liquid) are taken up by the plant and translocate to the root system to provide season-long control. It generally takes several weeks for impact to become apparent.
Contact herbicides (Aquathol Super K Granular, Hydrothol Granular and Weedtrine-D Liquid) only affect the portion of the plant that comes into contact with the herbicide. Plants usually die-back within a week, but some plants may grow back later in the season since roots stay intact. In general, herbicide treatments should target nuisance exotic species such as Eurasian Milfoil and have minimal impacts on most native plant species.
This involves cutting and removing vegetation. Mechanical harvesting (Water Weed Rake & Weed Razer) has the advantage of removing biomass and help slow the rate at which plant material accumulates. Harvesters have limited operational flexibility and can agitate bottom sediment and temporarily increase turbidity. Attempts to control certain plant types by harvesting may not prove entirely effective. This is especially true with Eurasian Milfoil due to the fact that this plant may proliferate and spread via vegetation propagation.
Milfoil weevil is an aquatic insect that is native to North America and appears to be common in the Midwest. The weevil has been found to feed almost exclusively on milfoil species. The milfoil weevil can be effective if adequate densities can persist through the summer and among years. However, many of the sites investigated have failed to sustain sufficient herbivore (weevil) density to affect control.
Involves using a combination of control measures. For example, many lakes use a combination of herbicide and mechanical harvesting. Herbicide treatments are performed early to control Eurasian Milfoil, and harvesting is conducted later to control other nuisance plants.
Aquatic plant control is an ongoing challenge. The approach or combination of approaches that work best in a particular lake depend on local conditions. Once an exotic plant has been introduced in a lake, a sustained effort is often required to ensure control.
Complete article found in “The Michigan Riparian”, (Vol. 47, No. 4), Fall 2012 by Tony Groves and Pam Tyning
A customer recently contacted us regarding reducing the large amount of muck in his pond. Below is his question and our response.
Hi…we have a 1/8 acre pond, about 5-6 feet deep on average, clean and swimmable but with about a foot of organic muck/sludge on the bottom (from 20 years of leaves, and other organic matter largely). What would you recommend as a starting dose, and how long do you think it would take before we see results. We were considering having the bottom dredged, but do you think your product could get as clean or nearly as clean overtime? Let us know what you think and what you recommend. Many thanks.
AquaClear Pellets are natural beneficial bacteria that are designed to reduce the decayed vegetation, reduce odor and clarify your water. AquaClear Pellets will not harm fish, birds, plants or humans. Best of all, kids and pets can swim the same day as application.
Your 1/8 acre pond with a maximum 6 foot depth is 5,445 sq. ft. with an average 3 foot depth. A pond this size would require 1.25 lbs. of AquaClear Pellets per treatment. Simply weigh out the proper amount of pellets and spread evenly over the pond surface. Each treatment will normally consume ½-1 inch of muck. Visible results should be apparent after 1 to 2 weeks.
Due to the large amount of muck in your pond multiple applications will be needed. Each 10 lb. bag of AquaClear Pellets will give you 8 weekly treatments.
They say bad luck comes in threes, and that is the case on the Santee Cooper lakes this year. A trio of invasive weeds, including one still so new that the state hasn’t officially declared it such, has literally taken root and continues to hold on despite the best efforts of Santee Cooper’s analytical and biological sciences department. Invasive weeds are not new to Lake Moultrie or Lake Marion. But they are pervasive.
This year is the 30th anniversary of hydrilla first being spotted in the system, in Lake Marion near Rimini. By 1994 it covered almost 45,000 acres of the two lakes — roughly 40 percent of the water surface. Aggressive, hydrilla-eating Chinese grass carp were introduced to the lakes in 1989 and finally made a dent in the problem in the mid-1990s. Maintenance stocking of the sterile carp became more routine in the 21st century, but a combination of events has led to a resurgence in hydrilla the past couple of years. Today, it covers nearly 5,000 acres, a far cry from its peak but still alarming growth from a few hundred acres just three years ago.
A second nuisance plant is the deceptively delightful-sounding water hyacinth, which first emerged in the early 1990s and is currently blanketing almost 1,500 acres. That’s a larger presence than in recent years, due to the mild winter. “It’s been around awhile, but it’s easy to control,” says Larry McCord, supervisor of analytical and biological sciences. In other words, it’s out there and it’s the least of his worries. McCord knows he’ll eventually stamp down the hydrilla again, too. He’s battling a shortage of carp in the marketplace right now, but as he finishes out his plan to stock 109,000 of the fish in the lakes this year, they’ll go to work on the hydrilla.
It’s the third plant, the not-yet-designated invasive weed, that continues to thwart his team’s best efforts at eradication: crested floating heart. If the water hyacinth sounds nice, the crested floating heart looks nice. Think Monet’s Water Lilies, but easier to duplicate since it spreads so easily. In fact, the plant’s comely appearance is likely how it first found its way to the lakes, McCord figures. Probably a well-meaning resident thought it looked pretty in a container garden or somewhere else, pulled one up and transplanted it. The leaves can develop their own root structure though, and it can spread just by a leaf breaking loose and drifting or being pulled on a boat propeller somewhere else. McCord says the latest survey shows the crested floating heart is covering almost 3,000 acres of the lake now, up 50 percent in three years. It could easily spread to be as big a problem as hydrilla was two decades ago. Scientists haven’t found a fish yet that can eat enough of the weed to control it. So McCord uses chemicals which have limited effectiveness. Getting the plant declared invasive by the state might help secure additional resources to battle it and keep folks who think it’s pretty from moving it to their backyard lakeshore. McCord has been working on getting that declaration since 2005. There’s real money involved in the fight, too. Santee Cooper is spending $1.2 million this year battling invasive weeds on the lakes, part of our overall responsibility for managing the lake system to promote native habitats, recreation and inland navigation. McCord’s team tackles the weeds with truck, airboat and helicopter applications of EPA-approved chemicals, and he’s cornered the market on grass carp now in the ongoing hydrilla war. At best, that’s enough money to hopefully keep the problem from getting bigger, although the crested floating heart is gaining acreage right now. “I hope people out there will notify us if they see new areas of the weed,” McCord says. “I hope they’ll try not to spread it, and I hope they’ll be patient as we work to get rid of it.”
This article by Mollie Gore of Santee Cooper Corporate Communications from Santee Cooper’s Powersource magazine.
A customer recently contacted us regarding applying Restore Liquid to his pond. Below is his question and our response.
Hi-I buy my Restore from you guys every year and have an application question. I know I’m supposed to wait until my pond reaches a certain temperature before application, but when I do this, Duckweed and Watermeal tend to get out of control. The pond I treat is relatively shallow (average 1.5 feet and about ¾ an acre) and mucky with some floating bog on it. How early can I apply my Restore? Since I had trouble keeping the Watermeal under control, I’m thinking I should use a higher concentration. Any words of wisdom so I’ll know how much to buy for this season?
Your ¾ acre pond with an average 1.5 foot depth is 32,670 sq. ft. or 1.125 acre-feet. A pond this size would require 9 oz. of Restore Liquid. As you may already know, Duckweed and Watermeal are both difficult to control. Water temperature is not crucial, treatment early is. For best results, apply Restore Liquid at the first sign of new growth when the small bright green grains begin to collect around the edge of your pond.
No need to apply a higher dose, but do break the total amount recommended into 3 separate treatments to extend the length of time solution is in the pond.
Mix 3 oz. of Restore Liquid with enough water to spray evenly over the water surface. Wait 14 days, mix a second 3 oz. of Restore Liquid with enough water to spray over water surface. Finally, after another 14 days, mix the last 3 oz. of Restore Liquid with enough water to spray the water surface. The solution will blend throughout the entire pond, stay in the pond at the required concentration and be absorbed by the small particles of Duckweed and Watermeal as they multiply. Particles will begin to lighten in color and often pick up a pinkish hue. Full control may take up to 90 days.
AquaClear Pellets are a second option to consider. AquaClear will not directly kill Duckweed or Watermeal but will strip nutrients from the pond that both Duckweed and Watermeal thrive on. By reducing the nutrient level the amount of new growth should be significantly reduced. Your ¾ acre pond would require 7.5 lbs. of AquaClear Pellets per treatment. A 50 lb. bag of AquaClear Pellets will treat your entire pond 6.5 times. Treat weekly for a minimum of 4 weeks or until the desired water quality is achieved. Sprinkle pellets directly onto the floating bog to also speed its decay.
AquaClear Pellets may negatively affect any herbicides you may be using. If you use Restore, wait three weeks after the final treatment prior to switching over to the AquaClear Pellets for the "muck".
Q---I’m considering buying a property with a spring-fed pond. Before I sign on the dotted line, what kind of maintenance considerations should I be aware of?
A---Spring-fed ponds are relatively rare. Water flows out of spring-fed ponds at all times, not just after heavy rains. Many people mistakenly think they have spring-fed ponds. During construction, water gushed into the dug pond area from what was assumed to be springs, instead what they saw was ground water flowing into the hole from veins of water–bearing sand or gravel. If, however, water is continually discharged through a pond's spillway, it is indeed a spring-fed pond.
The average life of a poorly maintained pond is 25 years. Without human intervention, new ponds gradually fill with silt and organic matter. As years pass, the open-water areas shrink, turning into a swamp or cattail bog. A well-maintained pond can last forever.
To keep any pond in good shape, it is important to remove trees and brush from the dam area on an ongoing basis. Evict burrowing creatures like beavers and muskrats to keep water flowing. Finally, manage excess aquatic vegetation.
To manage excess aquatic vegetation, first measure pond size, next identify weed type and finally, determine proper treatment options. Specific questions can be addressed by emailing us at weeds@KillLakeWeeds.com.
Most new ponds can be kept healthy by adding natural bacteria (AquaClear Pellets) on a regular basis. AquaClear Pellets will not kill anything but will strip nutrients and muck from the pond that weeds and algae thrive on. By reducing the nutrient level, weeds and algae should be kept at bay.
Complete article by Sue Weaver, Hobby Farm Magazine, Nov/Dec 2012