I like the idea of containing them, but think you will need to be vigilant to contain them. I would love to have a bunch of it and would convince my wife if I had a good plan. I would love to have them line my bank from one side to about half way to the point my boat house sits on. I would start at one end and come to my old boat house that my boat is hanging in (and stuck there, but will not tell that story now) and then some way block it's path to continue from there.
I am not sure that I wouldn't put them in containers that later I could take the dirt out of and replace with concrete and sink them in the buckets it grew in?? It does make a very nice place of crappie to get in. I put some in this lake starting about 4 years or so ago and the first ones I didn't make heavy enough so they turned over. Plan on using more concrete and put a pop bottle in the top to hold it up now. I will tell you when I put my first 4 in I went back the next day to one close to my house and fish were already in that bush. So I have no doubts that this makes a very good crappie hang out. I have a few pick for my old one and will post a one here.
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My First Boo Buckets and yes they may be a bit tall, but some went in deep water, others I should have made shorter....