I made this tree skirt for my daughter. The pattern was a free leaflet from a fabric store that closed about 35 years ago. A long time ago, I found this pattern on the net, but I don't know what the pattern is called so that you can hunt it down. Since it is just stars and square blocks with triangles on the four corners, it wouldn't be too hard to draft out to the size you would like your tree skirt to be. Or even substitute some other block you would like for the stars. I don't have the skirt any longer, so I can't measure out the squares for you to know what size these are.
I am thinking of making another in generic fabrics to use on my dinette table. Of course, not cutting the hole in the center. I think it would look very nice with a vase of flowers in the center, or a bowl of fruit. Maybe use some other block instead of the stars. How would it look in red, white and blue for the fourth of July? Now if I can just find the pattern in all my stacks of clutter.