I agree that there are lots of great choices in Ashe and Alleghany, as well as all of northwest NC. I applaud the OP for wanting to make an experience out of your choose-and-cut venture.
Our mountain home is near Banner Elk and Linville. My personal favorite is Twin Pines on Hwy 221 between Linville and Pineola. Been going there for years.
For those others who may want to do a web search for "choose-and-cut" tree farms, here's a better site than even the NC Christmas Tree Assoc. (

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Pick Your Own Christmas Tree