Here is a list I got off epicurean-hermit.com which is a site that lists foods that are safe for hermit crabs. The list was created for birds, so I believe it is a very good list for all types of critters. Maples on there too! I doesn't list apple trees, I know they are good too, as is willow and popular. Pine is safe for our mice only after is has been kiln dried. Kiln drying removes the harmful oils.
Safe woods
Cholla wood
Cork bark
Cypress (swamp variety, taxodium species)
Grape vine
Madrona
Mangrove
Manzanita
Maple
Oak
Pear
Pecan
Sycamore
Unsafe Woods
Apricot
Bitter Almond
Boxwood
Cherry
Cherry Laurel
Eucalyptus
Evergreen of any kind (pine, cedar, redwood, etc.)
Hemlock
Laurel
Nectarine
Peach
Plum
Yew