I set Christmas trees in 5 gallon buckets standing straight up in concrete. I trimmed the lower branches so that the bottom of the tree would sit flush on the bottom of the bucket. I left 2 inch stubs when I cut the lower branches to help hold the tree in the concrete and also hammered in 2 long nails into the trunk. I plan to loop a rope through the handle of the bucket to be able to lower the tree where I want it in the lake. If I don't get it in the right spot, I should be able to lift the tree with the rope and move it. Once I get it placed properly, I can just pull the rope out. Sounds easy, but I will find out this weekend.