There are more trees in the US now than there were 100 years ago.!
Ironically, the East Coast has had the greatest gains even though it was the most heavily logged area by European settlers in the 17th century.
Many factors are responsible. Conservation and preservation at national parks, responsible tree growing within plantations (which have been planting more trees than they harvest), the movement of the majority of the population from rural areas, and the tree planting efforts which started in the 1950s are all to thank.
Most importantly, 63% of the forest land in the US is privately owned and many landowners are leaving their land intact. On the flip side however, this is probably because activities like agriculture and logging have been taken overseas.