mini-planting area at base of tall trees on city streets
Is there a word that describes these roughly 3' x 9' gardens you see all over the city, often neglected and overgrown? I am looking for a book that discusses their challenges and shows examples. Can you suggest one? Thanks.
These plantings under trees are sometimes called tree wells, tree pits, or tree beds. Here is a publication about them from the Brooklyn Botanic Garden. https://www.bbg.org/pdf/tipsheets/2017_BBGCGtipsheet_streettreebedcare.pdf
The planting area between the street and sidewalk is also sometimes referred to as a "hellstrip" and there is an entire book devoted to gardening in areas like this. http://www.timberpress.com/blog/2014/04/what-the-heck-is-a-hellstrip-and-why-does-it-matter/
"Sidewalk Gardens of New York" might be another good reference book for you.