I like the tree design, but as others have said, I would do a bolt down. Here is a pic of a couple of table bases I did a year or so back. There is a lot of texture on the "wood" base to emulate the bark on the table top.Curly maple table base

Using small sections of pipe and forging out flares to fit can give a very realistic look. Congratulations and good luck.

Rick Sidebottom
Metal Artist

By the way - sorry bout the metric units.
I was taught that way at school, then my last employers just about broke me of the habit being good victorian types.
But when I started talking feet and inches to the client they came over all glassy eyed and bewildered.
Will Jones, www.ironwill.org.uk