NEWPORT, R.I. (AP) — On Newport’s south side, historic and opulent mansions sit on an avenue with mature trees that help cool the neighborhoods, clean the air and foster wildlife. On the city’s poorer North End, where some streets are dotted with subsidized housing, big trees are a lot fewer and far between. “People in this neighborhood aren’t receiving the benefits of trees,” said Natasha Harrison, executive director of the Newport Tree Conserv…