NANJING, China — Tall as a 15-story building, with a mighty trunk, crooked branches and kingly canopy of leaves, the London plane tree, Platanus x acerifolia, is prized by horticulturists and city planners as a “supertree,” immune to urban grime and smog.

But can it survive a development-hungry Chinese Communist Party? In Nanjing, a southeastern city of eight million people, the answer seems — for now — to be yes.

In a nation where homes and farmland are routinely chewed up for the sake of high rises and factories, a grass-roots campaign by Nanjing residents this spring to save hundreds of the trees, known here as the wutong, from a subway expansion might seem like a nonstarter. But the effort, organized mostly online, has led to a surprising compromise from local government officials.

It was not a shining example of democracy in action. But neither were ordinary citizens left fuming about power-drunk bureaucrats deaf to anyone below.