hello, just wondering if any of you specialists could give me some advice I'm a college kid, but I still enjoy taking care of the 'rents lawn. Dad has been with ChemLawn for a while now, but he just pays the bill. So we have their services available if you recommend I take advantage of that. (I've read about something called core aeration??) anyways, this is what the lawn looks like up close. I see a kind of buildup of brown material I was using this and this is what I pulled out after 15 minutes also, for added kicks, here's a video of what I was doing for 15 minutes. I was gently raking, then kind of digging the rake in the grass and pulling straight up to exhume the brown material, then gently rake away again. let me know if I just ruined the lawn, or whatever advice the gurus of grass can throw my way. thanks for any help!