photoshop help

[450robot]

ok, so i have this picture i took at the spartan race, and i want to find a way to make everything black and white, except for the rider and his quad

how do i do it?

and if that damn tree wasnt there, it would be the best picture i have ever taken!

[xander1027]

this is going to be really hard to do because the rider has a green tint from the trees going by so wen i tried it he looks fine but has a shade of green over him personally i like the way it is now. there is no real way to get ride of that tree u couldnt recontruct was behind the tree.

[mx428]

I think you desaturate the image then use the history eraser on the quad. Not positive though.