I have several flower gardens on our cottage property on Lake Superior. Two of them are really troublesome in that the plants develop a really tight root ball that looks like matted hair. I just dug up several of my roses which were looking unhealthy and moved them. When I dug them up, they were being strangled to death by this dense substance. Could the plant create this? Another area has the same problem and I have perennials trying to grow there. Other garden areas are just fine.

Any ideas what's happening here? Is it the plants or is it a soil condition problem? Hope someone can give me a hint. Thanks.