(A very interesting word, "boulevard", from 1700's French meaning an avenue built on a razed rampart. Also very interesting what that strip is called all over the U.S. according to Wikipedia. This strip name even turned up in the New York Times quiz that shows you "How Y'all, Youse and You Guys Talk". Just all around interesting.)
I rather like the terms devilstrip, furniture zone, and hellstrip and there is even a book written called Hellstrip Gardening: Create a Paradise between the Sidewalk and Curb.
Our old boulevard was filled with Liquidambar trunk and roots, ice plant, and African Iris. The sidewalk was a hazard - tilted concrete - from the roots snaking under to our lawn. It was really bad. Our neighbor chastised us for causing her husband to have to climb over the humps with his walker. The final straw was when the local teens started using it to get airborne on their skateboards. A true accident waiting to happen. The city no longer repairs sidewalks so we decided we needed to take this into our own hands. We removed the two Liquidambars and put in a couple of landing pads and a brand-new flat sidewalk. Heaven!