There are a variety of products that are available to control weeds in ponds and lakes. The specific type of pond weed killer or lake weed killer depends on the types of weeds that are growing as well as the size of the pond or lake. Different products are generally recommended for plants that are growing beneath the water as opposed to those that are growing on top of the water.
The critical determinant of which pond weed killer to use is the type of weed that is the target. One of the more common surface pond weeds is duckweed. Duckweed exists on the surface of a pond and is characterized by very small leaves that measure no larger than ¼ inch. If duckweed gets out of control, it is likely to cover an entire small pond and it can cut off the oxygen supply for any fish that exist in the small pond and result in death for these and other aquatic creatures. While raking of the pond is an option, a pond weed killer may be necessary to control this weed. There are several pond weed killers which when used according to directions are relatively safe. These herbicides act as very effective pond weed killer or lake weed killers and generally pose no extended risk to the environment if used properly.
Two other common surface pond weeds are mosquito fern and watermeal. As with the duckweed these possess very small leaves. Watermeal is the smallest seed-bearing plant in the world and is characterized by leaves that are less that 1/16 inch in size. Mosquito fern bears leaves that are no larger than one inch and the color may vary from green to red. These plants often co-exist with each other and with duckweed. A pond weed killer will effectively rid a small pond of these weeds.
There are a number of weeds that exist in ponds below the surface. Two relatively common weeds are American pond weed and baby pond weed. American pond weed has several leaves on a stem that are about 3-6 inches long. It grows from the bottom of a pond and these leaves can be present on the surface of the pond as well as below. Baby pond weed is a wiry plant that exists below the surface. It is green and has the appearance of tangled string when pulled up. Again a pond weed killer or lake weed killer will be effective in the control of this pond weed.
A critical element to bear in mind when using pond weed killers or lake weed killers is to accurately determine the volume of the water to be treated. Careful measurement is a must when using a pond weed killer to protect the environment while ridding the pond or lake of these weeds.