It might, repeat might, be a Stagshorn Sumach (Rhus typhina). They have those purple cone type things. If it is, and piccies will be needed to confirm, then get rid of it. It is a vicious, vigorous sucker creating plant. In some US states it is illegal to grow it other than in a container. It will ruin your lawn, putting out suckers that try to shoot. Your mower will cut the young leaves, and so it will make more. You will then finish up with a great knotty lump just under the lawn. Not one lump, but many. A neighbour of mine had one growing in his back neighbour's garden, maybe 100' from his house. When he came back from his hols a sucker was growing up INSIDE his lounge.
If it is that, dig it, and as many roots as you can out. Roots left in can become new trees.
Edit, shucks beaten to it whilst typing that.