We took over a commercial property this year, and there are several holes in the lawn that need to be filled & seeded. My guess is that they may be old tree stumps that rotted away. Do I put on my pre- then fill & seed like usual, or use no pre-emergent at all? Will the pre- affect my seeding if there's 2-5" of topsoil over the top of it? I'm thinking the seed won't be affected, what about you guys?