What Influences Water Quality

Effects of Aquatic Plants

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Aquatic plants are a valuable part of freshwater ecosystems, but they are often misunderstood. In fact, many lake residents would rather not have them in front of their homes. However, native aquatic plants provide many benefits:

When Plants are a Problem

If aquatic plants are so wonderful, why are they perceived as a problem by many lake residents? Most of the time, problems arise when plants are too numerous. They can:

The causes of dense plant growth are complex. Often it is attributed to increased nutrient input from around the lake or in the watershed from sources such as failing septic systems, fertilizer runoff, or agricultural waste. These increased nutrients can cause the natural process of lake aging (eutrophication) to proceed at an accelerated rate, and increased plant and algal growth is part of this process.

Another problem can arise if a noxious, non-native weed is introduced to the waterbody. These weeds can reproduce from plant fragments, as well as seeds and tubers. The plant fragments and seeds can spread to uninfected bodies of water in a number of ways:

  1. Recreational users carry plant fragments from one waterbody to another on boats, skis and other equipment.
    Weed covered trailer Where to check for water plants on car/boat
  2. Some people discard aquarium plants into local waterways.
  3. Waterplants sold to gardeners can carry non-native noxious weed fragments.
  4. Waterfowl can spread fragments.
  5. Wind, wave action and flooding can break off fragments of plants and spread them into an uninfested system.

Several foreign noxious species, such as Eurasian watermilfoil and Brazilian elodea, are very aggressive and can crowd out more desirable native vegetation.