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    Pond Weed Control in California

    Introduction

    Anyone who lives in California knows the state has lots of rules and regulations. That also rings true when it comes to aquatic weed control. In brief, California allows aquatic herbicides or algaecides to be shipped to addresses with private ponds or to licensed individuals. There is more to it, which is detailed below. Also listed are some of the most relevant aquatic invasive species in California and a few notable resources for pond owners.

    Aquatic Invasive Species in California

    Listed here are some of the most relevant aquatic invasive species (AIS) in the state. There are native plants that may become a nuisance in ponds as well. Whether dealing with invasives or natives, identification is the most important first step to control them.

    Use the resources below to help figure out which plants are in, on, and around the water. The next step is finding the best method of control, which varies with each plant or type and other factors: preferred herbicide application method, treatment area, timeline, cost, etc.

    Emergent:

    • Alligator weed
    • Amazon frog bit (South American spongeplant)
    • Giant reed
    • Uruguay water primrose

    Floating:

    • Coontail
    • Floating pennywort (not a problem yet, but it is a plant to watch out for)
    • Water hyacinth

    Submerged:

    • Curly leaf pondweed
    • Egeria
    • Eurasian watermilfoil
    • Fanwort

    California State Regulations for Aquatic Weed Control

    There are different rules around products that have EPA registration numbers and those that don’t. Products that have EPA registration numbers make pesticidal claims, which is why they must be registered.

    Products that don’t make claims of killing any plants or organisms can be sold and shipped to anywhere in California. These products include nutrient reducers such as pond dyes, PhosControl phosphorus binder, SparKlear nutrient reducer, and MuckMaid muck pellets.

    Herbicides and algaecides have EPA registration numbers because they kill weeds and algae and thus can be shipped to a California address with a private pond or to someone who has their QAL (Qualified Applicator License) with category F (aquatics).

    Ordering from Lake Restoration

    If you don’t have a QAL, the state wants us to save a statement from you that says: “The products purchased are intended for use at my home, and they will not be used in agriculture or in public parks and schools.” At Lake Restoration, when someone places an online order to be shipped to California, we go through a few steps:

    • If it is the first order with those billing details, we find the shipping address on Google Earth to see if there is obviously a pond there.
      • If there is obviously a pond, we measure the pond and save a screenshot, and then this person is considered approved to send products to.
      • If there is no pond, or it looks like it might not be a private pond, we put the order on hold and send the customer an email asking for a copy of the QAL license or the above statement. If we don’t hear back within a week, we void the payment and cancel the order. If we do hear back, the order is shipped right away.
    • If the order is from a repeat customer, we should already have the statement and aerial view screenshot saved, and then we ship everything out same day or next day.

    Registered Products in California

    Nearly all products Lake Restoration sells are registered in and can be shipped to California. The notable product that is not registered is surfactant. This is not an herbicide; it does not kill any weeds or algae.

    Instead, it is the wetting agent that breaks down the waxy cuticle on plants and helps the herbicide stick and penetrate the leaves and stems. The herbicides it is most often used with, Imox or Flumigard, are registered in the state and are frequently shipped there.

    You may be able to find a nonionic surfactant labeled for aquatic use at a local farm supply store or even Home Depot. If not, still use the herbicide since that’s what kills the plants. Without a surfactant, it may just take an extra treatment to get complete control of the targeted plants.

    CA Resources

    • University of California Agriculture and Natural Resources: This site showcases a handful of featured invasives and has a master list. It is backed by the USDA. This site has some good information but also has blank pages.
    • California State Parks: Division of Boating and Waterways (DBW): This is a great website where it is possible to choose categories of plants or the “Identify an Aquatic Weed” page that includes multiple pictures of each weed plus a description, growth period, habitat, and control information.
    • Lake Restoration Aquatic Plant ID and Weed Control pages: The Aquatic Plant ID page features a reverse image search that can be used by taking pictures of a plant and putting it into this page.
      • Then a list of possible matches will be given with percentages of certainty. It is also possible to search plants by name or just browse through them.
      • When on an individual weed’s page, there is a detailed description, multiple photos, and more information as well as a link to the weed control page. Weed control pages give manual/mechanical options as well as herbicide control options and tips for controlling that specific plant.
    • Lake Restoration staff: email Plants@LakeRestoration.com with close up pictures of the weed in question. Call 763-428-9777 option 2 to talk with our knowledgeable team who can answer questions about plants, help create personalized care plans, and answer shipping questions.

    Conclusion

    Whether treating invasive species in a pond or native plants, identification is the first step. Then determining what will best control those plants is important. State regulations only allow us to ship products to an address with a private pond or to individuals who have their QAL (Qualified Applicator License).