We're Losing Trees?

The  Boston 775 blog has a post on identifying the location of a Revolutionary war site in New York City.  There's a drawing by a British officer done from a specific spot which a researcher is now trying to identify.

The big challenge, it turned out, was that these parts of New York have many more thick trees than they did back in 1776, after over a century of farming.

That's true in  many areas: old photos of the area in which I grew up show the hills almost treeless, my memories are of some wooded areas plus trees in hedgerows, in the current century trees probably cover 50 percent or more of the area.