Hi, I found this online and thought it was too cool not to share.
http://www.loopix-project.com/
Go under models/freebies and you can find a giant collection of trees, shrubs, and flowers. I imported them into Prefab to remove the material info, then applied the textures setting alpha blend to true. They look really great in Away3D.
Anyway, enjoy!
(And thank the owner of the site)