Many of you mentioned that, to fight fleas naturally and chemical-free, I can either put down nematodes throughout the yard, or put down diatomaceous earth. I bought DE and put down a 50 lb bag a few weeks ago. It wasn't enough. We still have fleas. I have to do more in the house to help aid the fight. We're moving to Portland in a few weeks, and I was wondering if it would be possible to tag team the fleas with DE and nematodes? Or would the DE just kill the nematodes? If you know, please help! Thanks.