What did he say this morning...arbortorium?

This morning on the show (6:20am, only half way thru my first cup of coffee), I was talking about the Festivus Event in Battle Creek at Leila Arboretum still on despite the snow they were hoping for for the oudoor events.

Except instead of "Arboretum", I called it "Arbortorium".  Wondered if there actually was such a thing.

Thanks to Carol for this e-mail followup:

Also the word "arbortorium" was changed to arboretum in the early 1950s. The arboretum comprises some 18,000 trees and shrubs, over an area of approximately 

That's from Wikipedia.  OK, I know, Wikipedia.  But, I'm going with it this morning!