That may have been due to a burn ban.
When we where there we did, we asked and where told that we could as long as is in the fire pit or designated area. We cooked and kept warm all three days with a nice fire. They also sell the wood at the main office.
When there is no ban, yes you can. The store right across from the primitive camping sites even sell the wood. You're not supposed to collect your own wood for fires. Each primitive site has a grill with a fire pit.
I was there a few weekends ago. If there is no burn ban, you may use the fire pit at your campsite to start a fire. We had one both nights. But you need to bring your own wood. The rangers don't allow you to gather it from the ground.
i believe wood fires are a no go but if you have a little stove propane burner you should be alright.
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