I'm trying to draw (in Photoshop) trees from a place where it's possible to see 15 kilometers on one 1920 pixels screen.

The best I did was to make squares of trees, with shadow and Bevel and Emboss (with texture). I also added some noise, but it's far from perfect...

So... I don't see any tutorial precisely on this subject, because most of the maps here come with more details of the ground. If you have some lead, that'd be great

(Same thing for cities)