I have 2 young daughters, and want to start a tradition of planting a tree on or around each of their birthdays. My youngest's birthday is November 12th, so that one is obvious: OAK

But my oldest's birthday is May 31st and I'm struggling to think of a good tree to plant at that time. I know from direct experience that Silver Maple self-seeds around that time but that one seems tricky because it's a "live seed" so while that is a definite option, I'd prefer something that isn't on a clock lol.

The reason for choosing seeds rather than planting a rooted tree is literally just the amount of work required. Planting a seed is a short process, where planting a rooted tree is a lot of work that young kids would probably have no interest in. I'd love it, but they'd get bored before I even found the root flare lol.

Any ideas?