What's that stuff on the water?!!

Here we are rolling through June and lately Summer has been cooking! Lake temperatures have increased dramatically over the last few weeks. I was just finaly putting away my ice fishing gear and now the bluegills are already spawning! Aquatic plants in the lake are awake and growing vigorously, keeping us very busy as we race to produce the tailored 2005 nuisance plant and algae treatment protocols. Nobody's been as busy as the terrestrial plants though. It always amazes me how with just a little rain and sunshine trees begin to express full leaves, blossoms, and flowers. That brings us to the subject of this entry. We have recieved a handful of calls and emails from concerned and involved riparians about "stuff" on the water surface in isolated locations around the Canadian Lakes. Before addressing this "stuff", I want to thank those of you who are communicating with us through the Blog and the website. Having extra sets of eyes out there on all the different lakes makes our jobs easier. I also want to encourage those of you who have concerns, comments or questions to use this resource. We can only address your needs if we know they exist.
This "stuff" people are talking about is a combination of differnet terrestrial and aquatic plant and algae materials. In the more shelted coves and bays, we are seeing tree pollen and related reproductive trestrial debris floculating out of the air and landing on the water surface. Over time, this tree debris accumulates and blows into knooks and pockets along the shoreline. One place I commonly observed it accumulating last Tuesday and Wednesday was around large patches of lily pads, like in Far West.
This reproductive terestrial plant debris breaks down fairly quickly, especially with boat wake and wind/wave action. In the sheltered bays though, the process takes longer. Regardless of where or when it breaks down, it always releases tremendous amounts of nutrients (mainly phosphorus) in the process. To generalize, both aquatic and terestrial plants use nitrogen to form structure. They use phosphorus to produce flowers, seeds and pollen. So when the pollen breaks down, phosphorus is released and the life form most able to quickly take up these nutrients is filamentous algae. Fortunately, aquatic vascular plants take up some of this phosphorus too. Summit Laboratory is managing the lakes to favor low growing native non-nusisance aquatic plants such as Coontail, Elodia, Northern Milfiol and the beneficail colonial algae Chara to name a few. Our plan of action for the pollen/filamentous algae slurry is: 1. Allow enough time for all of the pollen to collect on the water surface and blow into accumulation zones 2. When the pollen is nearly completely broken down and the released phosphorus has been conferted to filamentous algae, apply a spot treatment of copper sulfate to only the isolated areas that warrent the treatment.
And what exactly are the scientific criteria for an algaecide (copper sulfate) treatment you ask. 1. Dominance of Blue-green algae 2. Dominance of filamentous algae 3. Dominance of nuisance species imparing community wide recreational goals 4. Significant reduction to water clarity due to dense planktonic algae blooms
Copper sulfate is highly affective at lysing algal cells and breaking up blooms of filamentous algae, but it is very non-selective too, meaning it has similar effects on non-nuisance and non-traget organisms. For this reson, we only perscribe copper sulfate treatments when they are warrented based on the criteria and Aquatic Nuisance Control only applies it to the defined target locations we prescribe. It is important to mention that copper sulfate does next to nothing to tree deris floating on the water. The best remedy for pollen coated water surfaces is a little patience and willingness to let nature do her recycling.
In this entry we included a map of the areas that Aquatic Nuisance Control will be treating tomorrow, June 10th. This algaecide treatment has no associated water use restriction associated with it. If you have any questions whatsoever, never hesitate to ask. Your Lake Managers, Joel and Tom