at that distance you dont need detail.., no hero trees.., use cards.., (do a google serch) they are planes with the image of the tree with an alpha to make the rest of the card transparent.., can use it for leaves, trees, people, whatever.., its an old architecture trick but used very often in film production.., stuff like blade runner.., maybe the inside on a space station.., an island.., whatever
take it easy and life will be easy