Trees, Shrubs and Conifers: Shelf/Conch type fungus invasion - help requested, 1 by JGinTN

JGinTN wrote:
I posted this on the master gardener forum & received a suggestion I should post my problem here because the fungus involved seems to come from a tree. I planted a flower & herb garden on a sunny spot in my yard in 2007. It's contained by the driveway which has a boxwood hedge lining it & stops at the side of the garage, the other border is a sidewalk. The grass in this area was always patchy & almost nonexistent, I've learned a large tree grew there but had been cut down before we bought the place. I have had wonderful success in getting daylilies, sage, basil, rue, hyssop, lavender, etc to grow here. But I noticed this weird stuff that suddenly appeared in 2008 at the edge of the bed, closest to the driveway & coming up around the base of boxwood hedge. Each year it is spreading inward, coming up in the daylilies now & even the herbs & flowers despite my best manual efforts to remove it. I've talked with the local extension service & they took samples. They actually came to the house when I told them it was growing up in my daylilies & surrounding them - they didn't think it should be growing in flowers. What I learned from the extension rep was that this is some type of "shelf" fungus or "conch" fungus that probably originated from a tree/trees that had been removed but the roots remained - they are decomposing in the ground & this is a fungus (?) that is living in the roots, that stuff I see in my plants is the way the fungus reproduces -- at least this is what I got from the conversation. He said it wouldn't hurt my plants but I could remove it since it is unsightly & smells. He said also said it wasn't toxic. It starts out as small, white bumps near the plants or in between the stems/fans of the plants & then grows into a cauliflower looking growth that turns into what you see below. It's very firm & difficult to remove. First it was just in the daylilies on the edge of the bed but now it's moving in & is appearing in the sage, the coreopsis, hyssop, etc. I try hard to pull it off of the plants/from the ground but it's impossible to get all of it without completely destroying the plants, plus it also pops up in the soil as it's moving in. It appears in early June, seems to grow actively through summer, then slows down in the fall & disappears until the next season. Any ideas on how to get rid of it? I'm afraid to take starts on any of the daylilies because I'm afraid I'll introduce this stuff to other beds - it's nowhere else in our yard. We do have mushrooms that randlomly pop up in yard but they are "normal" mushrooms like you'd see in the produce section & they don't spread like this stuff & engulf plants. I'd sure love to know deal with this once & for all since manually trying to remove it is incredibly time consuming & not very effective. Thanks. Here is what it looks like when it first starts...