Peeked at a tree or two today in zone 5/6 Hudson valley NY 1 mile from large body of water Hudson river. Chestnut is an early waking one, buds still small n quiet. cold coming in Weds / Thursday. If you got bare ground, good time to lime or frost seed.
Pears wake up before apples usually. Didn't check mine though.
Trees with higher bloom group numbers wake up later. Try to stick with group 3 or 4's. Liberty is group 2. Many crabapples wake up weeks before most commercial variety apples.