Like I tell others...Crappie cover has to serve a purpose for Crappie! It has to provide safe hiding, ambush pints, shade and rest area, or a food station. And then you try to provide cover in areas that connect their entire environment so it continually produces throughout the year.
So what does your cover provide? How many Crappie can fit in It? How many pieces of cover are needed to hold enough crappie to fish it, and if you take fish, what does it provide to attract mored fish so it will replenish?
And Nimrod is correct, treated wood is normally "treated" with Arsenic or other poisons to deter bugs and deterioration....not a good Crappie attractor!lol