You can make decent trees lots of ways, and easily with any of the sea foam type of products - Woodland Scenics have some packs, but they aren't cheap - see Woodland Scenics fine leaf foliage at http://www.woodlandscenics.com/ as an example.
Not the best pic but the only one I have handy of a tree that was made with the WS foliage.
If you just use the sea foam stems as trunks they are a bit thin. I prefer to use garden twigs or twisted wire frames for trunks. Normally I use WS and Heki foliage mats on wire or garden twig trunks.
Mike

If you just use the sea foam stems as trunks they are a bit thin. I prefer to use garden twigs or twisted wire frames for trunks. Normally I use WS and Heki foliage mats on wire or garden twig trunks.
Mike