FREQUENTLY ASKED QUESTIONS (FAQ)
In order to better serve our customers, Lakeland Restoration Services, LLC has provided the answers to some frequently asked questions about controlling plants in the water and common concerns regarding the use of herbicides.
A: Every state has its own noxious weed list and this list will tell you whether the plant is growing on land or in the water. Noxious weeds are plants which have been identified as aggressive, meaning they can disturb or damage native wildlife habitats, crop and domestic animal production and/or human activity.
Select a link below to find out more about noxious weeds in your area:
An online version of the Aquatic Plant Identification Manual can be accessed on the Washington State Department of Ecology website, or you can purchase the book from your favorite book seller.
A: The most invasive plant we have in Northwest waterways is the noxious weed, Eurasian watermilfoil (EWM), a plant that can clog a lake or river and cause damage to the native plants. Because EWM can grow faster than the native, water plants, it reaches the surface and blocks the sun from the native vegetation. If the native plants don’t grow, many water birds that use these plants for nesting will only have EWM, which can be a problem by tangling up baby birds.
Also, thick mats of EWM can slow water flows, warming the water (which can squeeze oxygen out of the water) and make the water environment conditions hard on fish. Fish can spawn in EWM, but once it gets real thick, the fish don’t have quality habitat.
Some other aquatic noxious weeds in the waters of the Northwest are curly leaf pondweed and hydrilla. Shore line noxious weeds include phragmites (an invasive grass), yellow flag iris and purple loosestrife (escaped ornamentals), and tamarisk (also known as salt cedar). Keeping a wide variety of native plants in the water and along the shore can make conditions better for wildlife.
A: We prefer you don’t remove EWM unless you can get the whole plant. EWM can grow from small pieces of its stem, so when it breaks up, from raking, pulling or chopping with boat props, the problem can get worse.
If you think you have EWM in your waters, contact your local Noxious Weed Board or office and let them know; they can conduct a survey and positively identify the plant and determine the treatment for control.
If pieces of EWM wash up on your shore, remove them upland so they don’t return to the water. You can get rid of EWM by putting it in the garbage or composting it in your landscape.
A: It’s not a good idea to remove native aquatic plants because established native populations can limit the spread of EWM into the area. Plus you have good fish habitat.
Some states, like Washington, require a permit to remove native plants along your shore line. Limited dock and beach access clearing by hand or rake can be done under a Washington Dept. of Fish & Wildlife (WDFW) “Aquatic Plants and Fish” pamphlet; contact them for more information.
A: The product we use in the water to control or kill water plants is an herbicide, the same products you use in your landscapes or pastures to control weeds.
The herbicide active ingredients used most often are Diquat, Hydrothol, and Aquathol. You can find great information about these herbicides at the National Pesticide Information Center (NPIC) website. They have information sheets about these and other herbicides.
A: The herbicide is applied either as a liquid product or a granular (pellet) product; it depends on the weed being controlled.
The liquid herbicide is applied from an airboat (much like those used in the Florida Everglades). A system of hoses is put into the water from the front of the boat, which are attached to a tank inside the boat. The tank is filled with the herbicide and water from the lake and/or river is sucked into the tank, mixes with the herbicide, and then is injected underwater to where the noxious weeds are located. Shoreline plants or emerged plants are sprayed with a hose and sprayer attached to the airboat, a backpack, or an ATV.
The granular herbicide is applied from a rotary spreader mounted to the front of the airboat. The spreader is a larger version of what is used on land (like a Scots® fertilizer spreader). With a large, open container that is filled from the top, the spreader distributes the granular herbicide across the surface of the water in a wide sweep. The pellets sink to the bottom where the aquatic noxious weeds are located, sticking to the leaves.
A: No, the herbicide will not affect your boat or dock.
A: Yes, treated water can damage landscapes if it’s used during a restricted use period. Some of the herbicides used for treatment of water plants are the same kind of chemicals used for weed control on land.
A: Depending on the type and amount of herbicide, these restrictions could be for 3 days to 10 days. Lakeland Restoration Services will provide updates on water-use restrictions through our website and toll-free phone line so you know when it’s safe to use the water again.
A: Once the herbicide is in the water, the restrictions for water use will be in place. Restrictions can include:
· No human or livestock consumption (drinking)
· No irrigating pastures or watering landscapes (including gardens, lawns, and flower pots)
· No swimming for 24-hours (Washington State restriction)
Sometimes there are no restrictions, again it depends on the type of herbicide being used and how much is being used.
A: According to the NDPES (National Pollutant Discharge Elimination System) permit, which is required to do aquatic herbicide treatments, you will be notified multiple times before a treatment occurs in your area (for more information about NDPES permits, contact the Environmental Protection Agency; in Washington State, the Dept. of Ecology; in Idaho, the State Dept. of Agriculture).
A mailed notice of intent to treat water plants will arrive between a month to (2) weeks before a treatment. This will give you basic information about the aquatic herbicide treatment and a contact number and/or website you can go to if you have questions.
Two days (48-hours) before herbicide is applied to the water, your dock and/or shore line will be posted with a notice/ flyer that tells you what herbicide is being put into the water, what the restrictions will be and when treatment begins. Use this time to do your irrigation or watering of landscapes.
A: If you have a fresh water source at your home for your animals, they will be OK. It’s always safer to keep your animals away from the water during the restriction period, but if they get into the water to swim, give them a rinse off with clean water.
The wildlife is living in the treated water which means that herbicides are being applied in such a way that birds, fish and other wildlife will be using the water to drink and swim in without harm.
A: When using herbicides, we are using a product made to control plants. When fish or waterfowl eat the plants or drink the water that is treated with herbicides, it passes through their bodies, much like cattle and horses grazing in a treated pasture.
The animal manure can have traces of herbicide and unless the manure is composted (heated and aged), the residue can harm plants when the manure is used in a garden. Fish and waterfowl manure is bio-degraded (composted) through micro-organisms in the water environment.
A: We get calls from organic nurseries or organic gardeners and we recommend they use a different water source when the treated water is under restriction. Once the water-use restrictions are lifted, they can use the water again because the herbicide is no longer present.
If you feel that using the water could cause future issues, we recommend you talk with your State Dept. of Agriculture or Natural Resource Conservation Service and contact the organic certification program representative.
A: Wells and aquifers are underground and any lake or river feeding these water sources passes through the soil. As contaminates in water move, the filtering action of soil reduces or eliminates those products. Most contaminates found in wells or aquifers are from the surrounding soil composition, unless someone has been using pesticides irresponsibly. We follow the label because the label is the law; permits from the State for herbicide use in the water are applied for every project.
The herbicides we use are being used in amounts known as parts per million (ppm) or parts per billion (ppb). For example, 1.0 ppm equals 0.013 ounces of product to 100 gallons of water.
A: When herbicides enter the water, they begin the process of changing or breaking down, just like composting.
How long an herbicide remains active in the water depends on things such as the amount of light present and the temperature. The process of breaking down is called bio-degradation and it happens in different ways.
There is photo-degradation, which means that ultraviolet (UV) light breaks the chemical bonds of the herbicide ingredient molecules. Each time these bonds are broken, the ingredient becomes less and less effective as a weed control. This is how herbicide residue lessen, becoming non-detectable over time. We do water sampling for herbicide residue during the project.
Microbial degradation occurs when tiny organisms that live in the water use the herbicide as a food source. Most all pesticides are organic compounds made of mostly carbon, hydrogen, nitrogen and sulfur; these compounds are food for microorganisms. As chemicals are applied, the microorganisms that feed on the chemical increase in number, eating the chemical and digesting it, breaking it down in the process.
Chemical degradation is when the herbicide is diluted in the water. When the herbicide is applied, it begins to lose its concentrated form immediately as it mixes with the water body.
Volatilization (evaporation) is the process of a chemical going from a liquid state into a gas state. When herbicides become a gas and release into the atmosphere, they no longer provide weed control.
A: A pesticide’s half-life (also known as degradation) is the time it takes for half of the initial amount of a pesticide to breakdown. If a pesticide’s half-life is 30 days, then half will be degraded in 30 days, one quarter in 60 days, one-eighth after 90 days, etc.