As I dug into the dirt I discovered a tough network of spidery roots everywhere. I could barely dig a hole. This is perplexing as NOTHING is really growing there except a sad little daisy patch that, as mentioned, has neither died nor flourished since I planted the potted plants last year. The dirt is mostly Miracle-Grow bags, and most of it was filled in this spring. I expected the dirt to be completely loose when I dug in--but it was completely filled with roots.

Any idea WHAT this could be? How can there be so many roots with no plants above ground at all? And any suggestions for getting rid of these without killing my existing (albeit sad) daisy patch?