Where West Market Street, with its brightly painted storefronts and makeshift stalls that sell odd trinkets to tourists, met the sturdier economic hub of Banker's Road, there grew the stunted mango tree.

It was an anomaly, out of place in the buzzing commercial landscape.

The city had decided, some decades ago, to let the tree be. Most of the elected members of the local bureaucracy felt it was harmless, and a few even felt it added a certain character to the locale.

No one could quite recall how old the tree was. The oldest...