I have these on a mature tulip tree and want to treat it. My thoughts are to:

1. Use Demon Max on the bark trunk of the tree.
2. Use Dominion 2L on the ground around the tree. I was planning on raking the mulch back some and spraying about a 20ft diameter circle around the tree.

Is this too much? How often would I need to do this? Once, every year, every other year????
Thanks.
Brian