The 250 acre New York Botanical Garden, established in 1891 in the borough of the Bronx, contains the last largest remnant of the old growth forest that once covered all of New York City. The old growth forest is considered the heart of the Garden. It contains oaks, American beeches, cherry, birch, tulip, and white ash trees.

This 50 acre area within the Garden is also known as the Thain Forest and has never been logged. It winds from the Bronx River to a forest of thick tree growth where Native Americans once hunted. Many trees are over two hundred years old. While the city has been systematically deforested, this area has remained the same since Europeans arrived in the early 1600's. It's here that beavers have made a reintroduction into NYC in 2007 after an absence of over two hundred years.

New York City, the most populous city in the United States also has the Brooklyn Botanical Garden which encompasses 52 acres and the 39 acre Queens Botanical Garden. Both are devoted to promoting the environment through educational and community programs.

In the heart of Manhattan, the most urbanized borough, lies the 343 acre Central Park. The fifth largest park in the United States, this oasis offers green space and recreation for up to 40 million visitors a year.

More Info: en.wikipedia.org