The best protection for lakes against invasive species is prevention, chiefly inspection and cleaning of boats before they enter our waters. The next best thing is to detect invasive species at the earliest possible stage, because that is when they’re easiest and least expensive to deal with.
For example, a Eurasian milfoil plant or two, noticed by an alert lake resident or visitor, can be removed cost-effectively and the spread of the plant greatly mitigated or stopped. On the other hand, a major infestation can require years and many thousands of dollars to treat and control.
We say that everyone should know techniques like CPR and the Heimlich maneuver, just in case we would need them someday to save a life. How about everyone learning the most common invasive species in case we might need to save, in effect, the life of a lake?
Are you well enough informed about major invasive plants to know them if you see them? And do you ever take a cruise around your lake with an eye peeled for them? I know I am not as knowledgeable as I could be. Here on Birch Lake we have rusty crayfish, but no invasive plants that I know of, because I have not looked carefully.
It’s not hard to get informed. The Wisconsin DNR website contains excellent information on aquatic invasive species, and so does the website of the Oneida County AIS program. So please, let’s all go and have a look. Meantime, could you recognize these plants?
Eurasian water milfoil
This plant has long stems that branch. Three to five featherlike leaves (usually less than two inches long) are positioned around the stems.
This one is dark green with leaves that have a reddish hue. Wavy margins on the leaves sides are reminiscent of lasagna noodles — except the margins have small “teeth.”
This invader is fairly new on the scene. It’s actually a kind of algae. Stems anchor themselves to the lake bottom with colorless filaments. The plant has pretty white star-shaped reproductive structures about the size of a grain of rice that may appear at or below the surface of the sediment. These structures can dislodge and sprout new plants.
Yellow floating heart
So pretty, yet so potentially troublesome. It’s easy to recognize this one by its floating heart-shaped leaves and showy yellow five-petal flowers.
Also quite pleasing to the eye, this one has sword-shaped leaves are triangular in cross-section. It has umbrella-shaped clusters of white-to-pink three-petaled flowers about an inch across.
The Oneida County AIS website has pictures and descriptions of these and several others. Just imagine an army of thousands of sharp-eyed lake residents and visitors ready to spot invasives as soon as they appear.
If we can reach that point, then we’re much better positioned to catch nuisance species before they proliferate. For the time being, we’d best be vigilant about keeping our boats free of exotic hitchhikers. Now, it’s time for me to take a slow canoe ride around Birch Lake.
Ted Rulseh resides on Birch Lake in Harshaw and is an advocate for lake protection and improvement. His Lakeland Times and Northwoods River News columns are the basis for a book, “A Lakeside Companion,” published by The University of Wisconsin Press. Ted may be reached at [email protected]