Question about plum tree?

We purchased a home this winter that had a 10-year-old plum tree in the front yard. When it got warmer and the tree began to leaf out, we discovered that the old owners had apparently planted some other bush/tree around the plum tree -- so from the ground up to three feet the foliage is green and then the purple plum tree foliage takes over. We just want the plum tree there (and to be able to see the trunk), so I pruned back the foliage on the interloper. However, I found that the trunks of this bush/tree are rather hefty (say 2-3 inches across) and, as they are right next to the plum tree, I'm afraid to dig up/pull up the roots, for fear that they have intertwined with the plum tree and will do some damage. How should I deal with this?

Question about plum tree?
Cat's right about pruning them out. Some plums and cherries are noted for suckering and are part of your tree, not something the previous owner planted too close. If the suckers were allowed to grow, there leaves would eventually turn purple like the parent tree, unless it was grafted to a green leaf root stock. Either way, just keep pruning away, and DO NOT use any kind of sealant! RScott
Reply:Usually plums are grafted to a more hearty root variety of tree. If this is the case and the root stock is growing just keep it pruned back. Use a pruning sealant to prevent rot if it is close to the ground and a good idea for limbs over 1/2 inch and larger.
Reply:You're right, diggin them out would damage the plum tree. Leave it be. Continue to prune away the new sprouts and suckers for the next few years. The old rootstock of the unwanted shrub will give up eventually.