Hi kgrow,
Where are you located? Knowing this helps when people give advice.
Based off the bud and leaf shapes, it looks like your mystery tree could be a mulberry. I could be wrong but that’s what my first thought was.
The blue spruce don’t quite look like blue spruce to me. I don’t see the right buds. And the needles, although bluish in hue, appear different. Perhaps you have eastern red cedar still exhibiting juvenile foliage.
also…. Not sure that’s a maple in pic 3. It looks more like sycamore or London plane tree. A close up of the buds would help identify it. Is the branching pattern opposite or alternating? Maples have an opposite branching pattern.
Lastly, tulip trees are great.
erc in photo 1. Blue spruce photo 2