One year of carbon sequestration from a mature tree == 1 or 2 days of commuting to the city 20 miles away that many people who are priced out of this town drive back and forth from.
Trees are great, and most places should plant more street trees. But if you preserve trees at the cost of building dense cities that are more environmentally friendly, you're doing it wrong. Dense cities also allow for more trees in actual wild lands outside of them, rather than sprawl.
In the US, transportation and heating are our biggest individual contributions to climate change.