Many states have an issue with blue green algae?
https://dnr.wi.gov/#AwN2 or
"Webinar about the health risks to be held July 16MADISON -- Heavy rains and high temperature are fueling the growth of blue-green algae, also known as cyanobacteria, in water bodies around the state, so the Wisconsin Departments of Natural Resources and Health Services are teaming up to present an informational webinar about the health risks of blue-green algae. Some blue-green algae can cause illnesses for people and animals who accidentally ingest or inhale it, or have prolonged skin contact with the algae."

As I understand it rain does not fuel growth of algae, but fertilizer, animal waste and sewage washed into water bodies does. It grips me to see cattle in the edges of streams , especially on public land.

I am not sure what causes the blue green algae, but can screw up both ideas. I have only seen it in one pond in my life. It was during a long drought, pond down low, no cattle, no fertilizer, with the only runoff to it being from a prairie hay field. I am still scratching my head as I type this because everything said to cause it is absent.

Rain water washes the nutrients to the lakes, which is what causes the increased liklihood of a bloom. Algea bloom also uccur naturally, its not always man made. Also, some cattle along a stream edge isn’t causing the problem. It usually the topical application of liquid manure that causes problems. Biggest factor is usually fertilzer washing out of the suburban yards.

I read that most of nitrogen pollution is in our soil naturally

That's what Scott Walker tells our DNR to put out there for the public to believe.

Cattle along a stream in a grazing system don't pose a risk. Its the confined feeding operations that extreme levels of nutrient build up is possible and confined feeding operations have to meet strict government regulations to operate.

https://cees.iupui.edu/research/algal-toxicology/bloomfactors

Above is one of several links one can read about algae and or blue green algae specifically.
Many seem to forget that it is phosphorus that is also a key to vegetation growth, especially in water where due to the hydroponic effects only 1/10 of the P needed to optimize most common land crops is needed to optimize vegetation growth in water. Also the article discusses the low Oxygen levels which occur in our deeper water during the summers. (fishermen know this as there are no fish there then). The P is released in the dissolved Oxygen and then as it rises to it can create more nutrients for growth. Also blue green algae prefers the hotter temps and can outgrow the other algae that prefer cooler temps. The algae can settle into the quiet and undisturbed shallow areas of the water.

Bryce

Lake St Marys has it here. They blame all the chicken and turkey farmers up north and maybe the crop farmers too. That run off goes to the lake and then in the summer they have blooms.

Then you started hearing of it in places further south than there.

https://lakeimprovement.com/pollution-issues-and-solutions-for-grand-lake-st-marys/

I've seen BG algae in WI and MN. Overly concentrated fertilizer is a major factor from what I've seen and read.

You know something is very wrong when every frog is out on the bank four feet from the water on a full sun 98F late July afternoon. They jumped back in just before my dog caught them, then hopped back out so hard on his heels that some landed *underneath* my dog. Those frogs wanted out of the water THAT bad. Pretty wild to see.

In Mo it's illegal to use felt soled boots for fishing because of this.

I respectfully disagree. Whether or not it causes blue algae growth I cannot say. But it certainly stirs up mud, deposits manure, and tramples plants that otherwise would help moderate water temperatures.

As for "grazing systems" national forests should not be so used.

Tiling, plain and simple. You can't bypass natural water filtration (ground soak, wetlands, etc) like tiles do without adverse effects to the end point (lakes and rivers). Also, plowing grass waterways isn't helping either. I have a marshy landlocked lake behind my house that has no farm drainage to it. I've never seen a big algae blooms in 30 yrs.

You Walker haters are a funny bunch. The algea in the Madison lakes is a direct result of liberals over fertilizing their yards. Those same liberal attack Walker for wetland being lost, but I would guess that if you live in a house in Madison, Waunakee, Sun prairie, Middleton, chances are 75 % you are a liberal and about 85% that a wetland was filled in to make room for your house. But you can just ignore that cause your union got taken away.

The discussion was specifically algae blooms.

Algae blooms come from many sources, fertilizer runoff and wastewater are big culprits. Discharging waste into a stream can cause algae blooms due to high concentrations of Phosphorous found in clothes detergent. The Talipia fish is good for cleaning up blooms, we eat them from the grocery store and they taste fine but they are a trash fish used for stream cleanup.

LOL!