Not sure if other crafters do this but I have little plastic bags with border punch left overs in. It comes in handy when you need circles like these or eyes on a punch art figure. So, I am unable to tell you where the circles on the Xmas tree came from other than from my little bag of circles !
This Dreamweaver stencil LL595 - Zig Zag Xmas Tree was sponged using Distress Inks onto cardstock which I got in the left over bin of an art supply store. They make up piles of offcuts and sell them for next to nothing. Most of my card toppers use these offcuts. The border punch used on the red cardstock is an old, un named EK Success one.