- Later divided into several forests, Yellowstone was the first national forest in the US.
- Kansas and North Dakota are home to national grasslands.
- The only tropical rainforest in the US National Forest System is El Yunque in Puerto Rico.
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It can be easy to take greenery for granted, but trees provide a range of benefits, from improving air quality to lowering air temperature. In the US, the National Forest System helps protect nearly 200 million acres of public forests and grasslands.
Here are 11 things you never knew about US forests.