Anyone out there have any good tips on getting rid of the air pollution you get over industry? I've een gone from dirty to manufacturing, mostly, and yet it still persists. I'm a tree fanatic, too. I put them everwhere, and if I have a 12x6 ind. zone, you can get that there's a 2x6 area of parks and grass aras where I plant trees. But how else can I get it down? Thanks.