Q.What Is Good To Plant At The Base Of Trees On A Sidewalk Tree. Weeds Grow There, I’d Rather Plant Something Nice
This is a street that leads to a main street. The trees are old but they are city property so no one takes care of the weeds. I like to pull the weeds on the ones near my house, but would like to replace them with something pretty that will grow. The soil is not the greatest, of course, though I could add some.

Certified GKH Gardening Expert
These articles should help:
https://www.gardeningknowhow.com/ornamental/trees/tgen/planting-garden-beneath-trees.htm
https://www.gardeningknowhow.com/ornamental/groundcover/gcgen/ground-covers-under-trees.htm