Evaluating Your Pond

The first step in water plant control is deciding whether it is really necessary.

As noted, a moderate growth of water plants is good for a pond. From a fisheries management standpoint, a healthy pond will have 10 percent to 20 percent of the bottom or surface occupied by aquatic plants. There should be a narrow band of underwater and emergent plants around much of the water's edge. These plants will stabilize the shoreline and attract fish from deeper water. If you pond fits this description, it's best to leave well enough alone.

If more than 20 percent of a pond or lake is plant-covered, there may be reason for concern. Excessive aquatic vegetation may cause fish kills during both the summer and winter, and can alter the balance of the fish community be providing too much escape cover for young fish. In this case, removing some of the aquatic plant cover helps maintain a healthy fish population.

Water plant control may also be advisable when aquatic plants begin to physically interfere with the intended use of a lake or pond, such as boating, swimming, fishing, irrigation or livestock watering.

What Good Are Water Plants?

Aquatic plants are the foundation of life in a pond or lake. Without them, most other organisms cannot survive. Plants keep the water oxygenated, provide food, cover and nesting sites, and stabilize the shoreline and bottom.

Fishing ponds benefit greatly from some water plants. Aquatic plants -- particularly microscopic algae -- are the critical first link in the food chain that may eventually produce lunker bass or other large game fish. Most fish don't actually eat aquatic plants; instead, they eat other organisms -- microscopic animals, aquatic insects, crayfish and frogs -- that either eat plants themselves or live on or around them. If the aquatic plants in a pond become too scarce (or too abundant), the entire aquatic community will be affected.

Another benefit is cover for young fish. Beds of vegetation give young fish a place to hide from predators. Without such escape cover, few would survive long enough to grow to a larger size. Aquatic plant beds also provide good fishing spots, because they attract adults of most fish species.

In short, if good fishing is your goal, the plants in you pond should be managed, not eradicated.