This looks like the ringless honey mushroom, Armillaria. It has popped up in many places this late summer and fall, due to rains we had earlier in the season. The fungus grows where there had once been a tree and there may be tree roots still left underground. The fungal growth of threadlike mycelium grows all spring and summer underground. When it has grown and stored up enough energy, it produces these mushrooms above ground.
The mushrooms can be raked or mowed over, to dislodge and break up. They are mostly water, so they will fade away, but may come back in a few weeks or next year, until the organic material in the soil is broken down. These fungi are decomposers in our ecosystem, and play an important role.
I recommend that people do not eat fungi they collect in the wild, unless they absolutely have it identified in person by an expert. There is some question as to edibility for these honey mushrooms. They are not harmful to people, pets, or the lawn turfgrass.
Thank you for contacting Cooperative Extension,