Aquatic life is changing dramatically on this body of water. The past three years have seen major developments of aquatic vegetation (weeds). This aquatic vegetation is known as Eurasian milfoil and has produced giant beds and mile-long areas to troll.

These weed-beds are now encountered in every bay that is associated with the main lake basin. There are also small, scattered weeds in the tributary arms, which means they are expanding rapidly. This Eurasian milfoil is one of the quickest spreading types of vegetation known in our waterways and can quickly take over a lake. The depth of this millfoil growth is from the surface to 13 feet deep on our “clear water” years. The floods and long periods of murky water will keep its growth a little shallower, nine feet is usually the maximum depth. As musky fishermen know, our quarry loves to hang around weedbeds. If you have ever ventured into the northern area of musky country, these weedy bays are one of the first places you begin fishing. Though we may think this newfound resource is wonderful, it has it's dangers and associated problems.

Eurasian milfoil was introduced from Europe in the early 1900's. It is found from mid-America eastward and also on the West Coast. It is a perennial that blooms from June through August. Milfoil grows very rapidly and forms dense mats that will grow to the surface. The plants have a long thin reddish stem about 1/8 inch in diameter with 12 to 20 small green leaflets in each leaf-section and they are arranged in groups of four down the length of the stem. Eurasian milfoil is kin to our native Northern milfoil. As with most organisms introduced into an unnatural environment they can wreak havoc once they are established, take zebra mussels for example. Once Eurasian milfoil has established itself it can become very difficult to control or remove. Because it grows so rapidly and creates such thick mats it can wipe out native plants by blocking sunlight and eventually killing them off completely. It can eventually dominate the entire water system. The method that Eurasian milfoil utilizes to reproduce is what makes it so successful. Plant fragments are its main source of reproduction. These tiny pieces can create an entirely new plant once they come in contact with suitable substrate. Eventually these single plants will form giant mats of vegetation. Most of the northern and Canadian waters warn you about the spread of organisms and request that you clean your boat and motor before putting it in another body of water. These tiny fragments of vegetation and other microorganisms are the reason for these requests.

Government agencies are trying a number of methods to control the spread of Eurasian milfoil which include hand and mechanical harvesting, water level manipulation and aquatic herbicides. Harvesting, whether by hand or mechanics is very difficult because of the fact that, any plant fragments left behind will produce a new plant and start the "spread" all over again. The yearly six-foot drawdown at Cave Run Reservoir will keep its' weeds at a manageable level, but this water manipulation is only viable on reservoirs. Aquatic herbicides are a last resort for the control of Eurasian milfoil because of its adverse effects on the ecosystem. There is an effective control method being tried in some areas. It is the use of aquatic insects such as the milfoil weevil, as the name indicates its preferred forage is milfoil. The number of considerable assets for using this insect for weed control are, that it is native to North America, the reduced costs and limited environmental impact.

As conservation conscious anglers, we need to help control this swift spreading vegetation. There are some ways we can refrain from increasing the contamination to other waters and slow the advancement of Eurasian milfoil at Cave Run Lake. Try not to run your big motor through the weeds, this chops up the weeds and the fragments will quickly root themselves in areas as the current or wind pushes them about the lake. When you fish these weedlines, try your best not to cast too deep into them and foul your lure. Every time you snag these weeds and remove them from the lure, you are assisting the advancement. Remember to check your boat before and after you leave a body of water that has any undesirable organisms such as Eurasian milfoil. If you are involved with fishing clubs, inform them of the dangers of Eurasian milfoil. Some weeds are good for the fishing and aquatic life, but too much of something can also be bad. By putting forth this extra effort you can help save your fishing hotspots and keep them from becoming weed-choked.