This is probably the best use of Christmas trees (though it’s up for debate whether it’s a good idea to cut down spruce trees to begin with).
Side note: it was hard to find this story on a website that’s not exclusive access or enshitified. Even the company who built the turbine (#Modvion) has a tor-hostile website themselves.
According to the BBC Newsroom they use glue instead of bolts to hold it together.
This article is claiming that the blades are still fiber glass: https://interestingengineering.com/innovation/worlds-tallest-wooden-wind-turbine