Tweezers are in...perfect for adding the dead branches
Clear Hot Glue works well for adding dead branches
"Japanese" Awl Tools...
Hemostats are great for holding trees while "planting" on the layout. Much better than using your fingers as they allow you to place trees closer together while keeping knuckles and fingers from breaking carefully placed dead branches. The jaws have ridges. Once you try them, you'll be gripped!