>> If it helps, Uwharrie National Park is 159.420 MHz, PL 131.8.
I believe you have agencies confused. 159.420 / 131.8 is a N.C. state park channel, and may be used at Morrow Mountain State Park. The channel is used at numerous locations, so someone monitoring the frequency
Uwharrie National Forest communications would take place on federal frequencies ... 168.725 / 110.9 R has been the channel most-commonly associated with that location. 168.025 - with various PL tones - seems to be a common L-E channel for national forest property.
Morrow Mountain State Park is a separate location from Uwharrie National Forest, with the Pee Dee River dividing the two properties:
http://www.cs.unca.edu/nfsnc/recreation/uwharrierecmap.pdf