According to their website, the Schulman Grove Visitor Center opened for the summer season on June 8th. Unfortunately, it doesn't list the hours of operation, when it opens and closes daily.
Call the visitor center before you go. This year at that elevation, there may still be snow up there!
If I am not mistaken, the Visitor's Center is open 9 am to 5 pm. However, you may go through one of the three trails anytime. It is a wonderful place to visit with trees older than 5,000 years old.
I think it's 10:00. If not. It 9:00
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