separate the GRF is possible?

[sunshare]

In the settings window GRF can add a line to group or separate the GRF that have the same characteristics?

[Sylf]

Yes.
http://www.tt-forums.net/viewtopic.php?f=67&t=70779

First 2 posts in that thread mentions 3 different sets of NewGRF that will let you do it.

[sunshare]

Thanks for responding !!

Not to open another topic I ask is possible to remove the trees of a scenario?