I'm wondering what kind of tree this is in my backyard:
Looks like a Photinia.
Could also be Florida Anise. Photinia should be bushier than that.
Florida anise has a completely different flower.
purpleinopp hit the nail on the head. As esh_ga said, Florida anise (_Illicium floridanum_) has a completely different flower--dangling, star-shaped, maroon--like a lady's eardrop, with a fragrance like a wet dog--hence its common name: Wet Dog Plant. It's one of my favorite native plants. Ours is abloom as I type.
You're welcome. I've been on a "wrong streak" & almost didn't post this one. Agree with donna it's straggly, though. Probably not enough light now that the trees around it have gotten so big. I only notice them in full or nearly-so sun.